Sergey Pavlovich Nepobedimy (Russian: Серге́й Па́влович Непобеди́мый; September 13, 1921 – April 11, 2014) was a Soviet designer of rocket weaponry. He was the Head and Chief Designer of the Kolomna Mechanical Engineering Design Bureau (1965-1989). Born in Ryazan, USSR, he graduated from Bauman Moscow State Technical University in 1945 and was directed to the work at SKB-101 (KBM, currently FSUE «KB Mashinostroyeniya») of Boris Ivanovich Shavirin.

He was the principal constructor of:

• anti-tank systems «Shmel» (1960), «Malyutka» (1963) and later, the semi-automatic «Malyutka-P» (1969);
• «Strela-2» (1968), «Strela-2M» (1970), «Strela-3» (1974), «Igla-1» (1981), «Igla» (1983);
• supersonic anti-tank guided rocket system «Sturm» - «Sturm-B» for the helicopters (1976) and «Sturm-C» for the vehicles (1978); «Ataka» (seriously modernized «Sturm») and first double-channeled Khrizantema.
• tactical rocket complexes TRK "Tochka" - with SBCh, OFBCh (1975), with KBCh (1977), with G (1979), with F-R (1982) and Tochka-U (1988), operative-tactical rocket complex OTRK "Oka" (1980).
• active armored vehicle defence system KAZ "Arena"

In 1989 after the INF Treaty, which eliminated all Soviet OTRK "Oka" (though formally they were not mentioned in the treaty) Nepobedimy stepped down as Chief Designer and retired from KBM. From 1990 until his death he worked in the Moscow Central Scientific Research Institute of Automatics and Hydraulics ad as the Chief of the scientific and technical center "REAGENT". He was the author of more than 350 scientific works, patents and one discovery. He died aged 92 in 2014.