The 1917-18 PCHA season was the seventh season of the Pacific Coast Hockey Association. Season play ran from December 28, 1917 until March 8, 1918. The season was reduced to 18 games per team. The Seattle Metropolitans club would be regular-season PCHA champions, but lost the play-off to Vancouver Millionaires. The Millionaires then played in the Stanley Cup finals series against Torontos, NHL champions. Toronto would win the best-of-five series 3-2 to win the Cup.