The 1986 Monaco Grand Prix was a Formula One motor race held at Monaco on 11 May 1986. It was the fourth race of the 1986 Formula One World Championship. The Monaco circuit had been modified from the year before: the chicane after the tunnel now had three turns and was renamed the Nouvelle Chicane.

The race was won from pole position by Frenchman Alain Prost, driving a McLaren-TAG. This was Prost's third consecutive Monaco win. His Finnish teammate Keke Rosberg finished second, with Brazilian Ayrton Senna third in a Lotus-Renault.

This was also the last Grand Prix for Italian Elio de Angelis, before his fatal testing accident at Paul Ricard three days later.