Born to Thomas, a union official and Katherine, a homemaker, Joey is the youngest of nine children, (Judy, Alice, Susan, Tricia, Carol, Jean, Kate, Tommy, and Joe) in an Irish-American Catholic family. He shares the same birthday as his sister Carol. One of his sisters, Judith McIntyre, is an actress.

Just before his 12th birthday, he joined New Kids on the Block, replacing Jamie Kelly. Since the other four members of the group were already long-time school friends, he initially found it difficult to mesh with the group. The New Kids on the Block became one of the most successful boy bands to date, producing two number one albums on the US Billboard charts. In 1991, Forbes magazine listed the band as the highest-earning entertainers, beating the likes of Madonna and Michael Jackson. The band eventually disbanded in 1994 following a media backlash and thus the declining sales. The band's music continues to sell overseas and the band itself is regarded as a pioneering act today.

Following the group's split, McIntyre busied himself with songwriting and sought a record deal. He made his acting debut in the film The Fantasticks, which was based on the long-running off-Broadway musical. This 1995 film, starring Joel Grey and Jean Louisa Kelly, was released in theatres five years later.