Gallagher was transferred to the main squad in 1985, in 1987 he helped Dundee United reach the UEFA Cup final, in 1987 and 1988 he played in the Scottish Cup final. On May 17, 1988, Gallagher made his debut for the Scotland national team in a match against Colombia at the Rose Cup.
Kevin Gallagher became a player in the youth team of Dundee United in 1983, when this club, under the guidance of coach Jim McLean, won the Scottish First Division and reached the semi-finals of the European Champions Cup.