Seven ships of the British Royal Navy have been named HMS Myrmidon after the Myrmidons of Greek mythology.
The first was a 22-gun sixth rate in use from 1781 to 1811. The second was a 20-gun sixth rate launched 1813 and broken up 1823. The third was an iron-hulled paddle gun vessel in service from 1845 to 1858. The fourth was a wooden-hulled screw gun vessel, launched in June 1867 but completed in October as a survey vessel, and sold in 1889. The fifth was a destroyer launched in 1900 and lost in a collision with a passenger ship in 1917. The sixth was a destroyer launched in 1942 and loaned to the Polish Navy in that year, and as sunk in 1943 by . The seventh was a minesweeper launched in 1944 and broken up 1958.