Watkins signed with the Montreal Alouettes of the Canadian Football League in June 2004. He played in four of the first five games but missed the rest of the season due to a shoulder injury. In 2005, he recorded his first touchdown, his first 1,000-yard receiving season and his first CFL All-star selection. He was part of the 2005 Alouettes' foursome of 1,000-yard receivers, tying the record (set by the 2004 Alouettes receivers of Ben Cahoon with 1183 yards, Jeremaine Copeland with 1154 yards, Thyron Anderson with 1147 yards, and Kwame Cavil with 1090 yards) for most 1,000-yard receivers on one team in a season. Kerry Watkins' 1364 yards receiving on the 2005 Alouettes team combined with the performance of Watkins' fellow Alouette receivers Terry Vaughn (1113 yards), Ben Cahoon (1067 yards), and Dave Stala (1037 yards) making the 2005 Alouettes only the second team in CFL history to have four receivers on one team reaching the 1,000-yard receiving mark in one season.