Why is Iran ditching Russian Su-35s for Chinese J-10C jets? Tehran's urgent military upgrade explained

Iran has reportedly stepped up talks with China to buy dozens of Chengdu J-10C multirole fighter jets, shifting course from a troubled deal with Moscow for the Su-35 aircraft. This comes as Tehran races to modernise its ageing air force in the face of mounting threats from Israel and the US. According to a report by The Moscow Times, Tehran is now in advanced negotiations to purchase 36 J-10C aircraft from China. The move comes as Iran's planned acquisition of 50 Russian Su-35 fighter jets has stalled, with only four aircraft delivered since the 2023 agreement. Iran’s push for modern warplanes has gained urgency following last month’s joint Israeli-American aerial campaign, which struck several Iranian sites, including nuclear infrastructure.

Chinese Chengdu J-10C vs Russian Su-35

As per reports, Iran has long been interested in the J-10 series and has tried acquiring 150 units as early as at least 2015. However, as per Militarnyi, that deal fell through due to payment disputes — China insisted on foreign currency, while Iran, under tight sanctions and low on hard cash, offered oil and gas as barter. A now-lifted UN arms embargo had further complicated the talks.

The Chinese J-10C, a 4.5-generation fighter compatible with long-range PL-15 air-to-air missiles, is already in service with the Pakistani air force and is considered a cost-effective and capable alternative to the Russian Su-35. What's more, the 4.5 generation single-engine fighter plane happens to be significantly cheaper than the Su-35 by around $40-60 million.

Why not the Su-35?

Iran's deal with Moscow for Su-35s, signed in 2022, was seen as a major step in rearming the Islamic Republic's air force. However, the agreement has suffered repeated setbacks. Despite official statements from Tehran that deliveries would begin in early 2023, only a handful of aircraft have materialised. In March 2025, it was reported that a batch of Su-35s originally slated for Iran had instead been redirected to Algeria.

Iran's outdated fleet under strain

While Iran, as of early 2025, had around 150 fighter planes in service, the fleet consists largely of ageing American aircraft procured before the 1979 Islamic Revolution, including F-4 Phantom II (64 units), F-5E/F Tiger II (35) and F-14A Tomcat (41). Many of these planes, as per reports, are either non-operational or require constant maintenance to remain flight worthy. The air force also operates around 18 MiG-29A/UBs acquired in the late 1980s and early 1990s, but these too are showing their age.

Over the past decade, Iran has relied heavily on domestically produced surface-to-air missile systems to form the backbone of its air defences. But during the so-called "Twelve Day War" — the name unofficially given to the recent Israeli-American strikes — these systems were swiftly suppressed by Israeli air defences.