China Surpasses U.S. in Nuclear Submarine Production, Raising Strategic Concerns for Washington

China is accelerating the construction of nuclear-powered submarines, launching more vessels than the United States over the past five years, a new think tank report warns. The surge threatens to undermine Washington’s long-standing dominance in undersea warfare and reshape the balance of naval power in the Indo-Pacific.

According to the International Institute for Strategic Studies (IISS), the People’s Liberation Army Navy (PLAN) has expanded its nuclear-powered submarine fleet with both ballistic-missile and attack submarines. Between 2021 and 2025, China launched 10 nuclear-powered subs, surpassing the US’s seven, while also exceeding the tonnage of new vessels—79,000 tons compared with America’s 55,500.

A Rapid Shift in Naval Capability

This marks a stark turnaround from 2016–2020, when China added only three nuclear-powered submarines (23,000 tons), compared with seven launched by the US (55,500 tons). Satellite imagery of shipyards underpinned IISS’s estimates, as Beijing does not publicly disclose fleet numbers.

While the US still retains a numerical and operational edge in its active-duty fleet, China’s pace of construction is narrowing the gap. As of early 2025, China had 12 active nuclear-powered submarines—six ballistic-missile boats and six guided-missile or attack subs—alongside a large conventional submarine fleet of 46 boats. By contrast, the US maintained 65 total submarines, including 14 ballistic-missile vessels.

Implications for Washington and Global Security

Analysts say the rapid expansion of China’s undersea capabilities could challenge US naval dominance in the Pacific, complicate deterrence strategies, and heighten tensions amid rising geopolitical competition. The report highlights the strategic importance of monitoring shipyard developments and fleet deployment as Beijing continues to modernize its military.