21st Century Business Herald reporter Zhao Yunfan
From less than 20 yuan per core kilometer at the beginning of 2025 to breaking 83.4 yuan per core kilometer in March 2026, the spot price of mainstream G.652.D single-mode optical fiber has increased by over 400% in just over a year, reaching a nearly seven-year high.
In the A-share market, the rise in optical fiber prices has driven a surge in related industries. Wind data shows that as of April 14, the Wind Optical Fiber Index has risen by 85.96% this year, approaching last year's full-year increase of 98.32%. Among leading individual stocks, on the basis of a 289% increase last year, Yangtze Optical Fibre and Cable Joint Stock Limited Company (601869.SH) has seen an increase of 213% this year.
Unlike previous cyclical fluctuations driven by investments from telecom operators, the core engine of this round of price increases is still attributed to the &#34;old friend&#34; in the secondary market—AI and computing power demand.
To meet the low-latency and high-bandwidth interconnection needs of computing clusters, optical fiber has transitioned from past &#34;cross-building, cross-street, cross-city, cross-continental&#34; long-distance transmission to becoming a mainstream transmission medium at the meter level for &#34;cross-rack&#34; connections. According to data from the UK Commodity Research Unit (CRU), global demand for optical fiber and cables in data centers is expected to increase by 75.9% year-on-year in 2025, with the proportion of AI-related optical fiber demand expected to rise rapidly from less than 5% in 2024 to 30%-35% by 2027.
Based on the overall demand expansion of computing clusters, the price increase and high-end development of communication interfaces (such as optical modules) have directly forced the &#34;fiber-to-copper&#34; substitution, and the application, research and development, and commercialization of specialty optical fibers (ultra-low loss large effective area fibers, multi-core fibers, hollow-core fibers, few-mode fibers) have entered a fast-paced stage.
Even the rise in copper prices is testing the short-distance interconnection logic of computing clusters that were previously centered around copper wires.
Replacing Copper with Fiber?
The logic behind the rise in optical fiber prices primarily revolves around the cost-performance ratio between copper wires and optical fibers.
From an application boundary perspective, the effective transmission distance of copper cables such as DAC and AEC is limited, suitable for interconnections within racks or short-distance interconnections between racks. Its core advantages are: compared to optical fibers, copper cables are cheaper, consume less power, and have higher reliability, making them well-suited for the high-density, short-distance interconnection needs of AI data centers.
Some brokerage research reports indicate that when the transmission distance exceeds 7 to 10 meters, the cost advantage of copper cables will gradually diminish—copper cable costs will significantly increase with transmission distance, while the cost sensitivity of optical fibers and optical modules to distance is lower, making their cost advantage more pronounced over long distances.
For scenarios where the transmission distance exceeds 100 meters and requires 10 Gigabit or even higher bandwidth, especially for the massive interconnections within and between racks in AI data centers, the stability and scalability advantages of optical fibers in long-term use are highlighted, and their total lifecycle cost-effectiveness is surpassing that of copper cables.
From the perspective of its own industrial logic, the capacity bottleneck of optical fibers has, to some extent, opened up the upper limit of the price increase
The core raw material of optical fibers: optical fiber preform (optical rod) occupies the high point of the industrial chain's value and technology, accounting for about 70% of the optical fiber cost, but its expansion cycle lasts 12-18 months. After the previous price war cleared out excess supply, the global leading manufacturers' production capacity has approached full-load operation, and capacity is prioritized towards higher value-added specialty optical fibers, which objectively squeezes the supply of ordinary scattered fibers.
Guosheng Securities pointed out that in the context of supply not meeting demand, customers are insensitive to price, leading to this steep price increase curve.
At the same time, the underlying logic of copper cables being suitable for short distances faces correction in 2025 when AI computing power demand surges, but precious metal prices also soar. As of April, global copper prices have risen by about 20% compared to prices before October, but the price increase for copper cable finished products seems insufficient, and there is a risk of restructuring in the market supply and demand structure.
The coexistence situation may continue
Of course, copper wires and optical fibers will continue to pull each other in the microeconomic perspective of computing power and coexist in the long term.
Huatai Securities' research report analyzes that high-speed copper connections have significant advantages over optical connection solutions in AI short-distance interconnection scenarios. The DAC solution has lower costs, more stable performance, and lower power consumption compared to the AOC solution. In practical applications, both NVIDIA and Huawei's super nodes use a large number of copper connections in cabinet-scale interconnections. This indirectly confirms that in specific scenarios of AI data centers, the physical economics advantages of copper cables have not been completely surpassed.
Kuyuan Securities believes that AI will take over telecom demand, and the global optical fiber market is entering a period of simultaneous volume and price increase. According to CRU's forecast, global optical fiber demand will rise to 880 million core kilometers by 2027. In terms of price, the spot price of China's G652.D bare optical fiber reached 83.4 yuan/core kilometer in March 2026, with a cumulative increase of over 400% since May 2025. The prices of similar products in the European market also increased by 136% month-on-month and 159% year-on-year compared to January, indicating that the trend of optical fiber price increases has spread globally, and the supply-demand gap is expected to widen to 15% in 2026-2027.
Guotai Haitong Securities' research report believes that compared to traditional data centers, the optical fiber demand of a single intelligent computing center can reach several times or even ten times more. A typical 10,000-card GPU cluster requires tens of thousands of core kilometers of optical fiber just for internal server interconnection. It predicts that the proportion of optical fiber demand in AI-driven data centers and DCI (data center interconnection) scenarios is expected to surge from less than 5% in 2024 to 35% in 2027.
Despite the high industry prosperity, risks are also accumulating. On April 13, the stock price of Yangtze Optical Fibre and Cable fell by 3.95%, closing at 369.18 yuan/share, indicating a divergence in market sentiment.
In a stock price fluctuation announcement on March 27, Yangtze Optical Fibre and Cable warned of risks, stating: &#34;Currently, the supply and demand structure of the domestic and international optical fiber and cable market has improved to some extent, but the stage price fluctuations of some products need to be comprehensively judged in conjunction with future market conditions and the company's business situation. The proportion of new optical fiber products related to internal and interconnection of data centers currently accounts for a small share of the total global market demand. We urge investors to pay attention to investment risks and make rational decisions.&#34;
The release of production capacity on the supply side is another uncertain factor. According to a research report by CITIC Construction Investment, since the third quarter of 2025, the price of optical fibers in the Chinese market has continued to rise, reflecting improved demand and an overall tight supply. However, once the new production capacity is concentrated and released in 2027, the supply-demand pattern may reverse again.
In addition, the iteration of copper cable technology cannot be ignored. Broadcom CEO Chen Fuyang stated at the earnings conference in early March 2026 that as they move towards 400G SerDes in 2028, Broadcom's XPU customers are likely to continue using direct-attach copper (DAC) cables. He emphasized that optical fiber solutions are more expensive and require more power consumption

515880

515050

159583

The price of optical fiber will be less than 20 yuan per core kilometer at the beginning of 2025, and will exceed 83.4 yuan per core kilometer by March 2026, an increase of over 400%. The A-share optical fiber-related industry has also risen, with the Wind Optical Fiber Index increasing by 85.96% this year. This price increase is mainly driven by the demand for AI and computing power, and it is expected that global data center optical fiber demand will increase by 75.9% year-on-year in 2025. Optical fiber is gradually replacing copper cables, especially over transmission distances exceeding 7 meters, where the cost advantage of copper cables is gradually disappearing

腾讯新闻 - 财经

Guotai CSI All Share Communications Equipment ETF

ChinaAMC CSI 5G Communication ETF

Fullgoal CSI Communication Equipment Thematic ETF

YOFC

NVIDIA

Huawei

Broadcom

NVIDIA Corporation

Behind the rise of the optical fiber concept, is "optical fiber replacing copper" true?