Otgonbayar is a Mongolian surname and given name. Notable people with the name include:
Dambyn Otgonbayar (born 1973), Mongolian guitarist Ishdorjiin Otgonbayar (born 1968), Mongolian football coach Luvsanlkhündegiin Otgonbayar (born 1982), Mongolian runner Otgonbayar Oyunbaatar (born 1993), Mongolian footballer Ravsalyn Otgonbayar (born 1955), Mongolian boxer