The 1971 National Soccer League season was the forty-eighth season under the National Soccer League (NSL) name. The season began in early May and concluded in October with the Canadian Open Cup final where Toronto Croatia defeated Challenge Trophy champions Vancouver Eintracht. The Croatians would secure a treble by successfully defending their regular-season title, and defeating Toronto First Portuguese for the NSL Championship. The NSL Cup was successfully defended by Toronto First Portuguese who defeated Sudbury City.