The 1981 FIA Formula One World Championship was the 35th season of FIA Formula One motor racing. It featured the 1981 Formula One World Championship for Drivers and the 1981 Formula One World Championship for Constructors, which were contested concurrently over a fifteen-race series that commenced on 15 March and ended on 17 October. Formula One cars also contested the 1981 South African Grand Prix, although this was technically a Formula Libre race and was not part of the Formula One World Championship.
　　The 1981 championship was the inaugural FIA Formula One World Championship, replacing both the original World Championship of Drivers and the International Cup for Constructors. Teams were now required to lodge entries for the entire championship, and a standardised set of rules would be in place at every championship race, while the FIA would also set the prize monies.
　　Nelson Piquet won the Drivers' Championship, claiming the first of his three Drivers' titles, while Williams won the Constructors' Championship for the second consecutive year.