Bell began his career in 1979 playing for the Manukau Magpies in the Auckland Rugby League competition.

[7] Dean Bell played at centre in Leeds' 18–10 victory over Widnes in the 1983–84 John Player Special Trophy Final during the 1983–84 season at Central Park, Wigan on Saturday 14 January 1984.

[12] Dean Bell played at centre and scored a try in Wigan's 18–4 victory over Warrington in the 1986–87 John Player Special Trophy Final during the 1986–87 season at Burnden Park, Bolton on Saturday 10 January 1987,[13] played on the wing in the 12–6 victory over Widnes in the 1988–89 John Player Special Trophy Final during the 1988–89 season at Burnden Park, Bolton on Saturday 7 January 1989,[14] played at centre in the 24–12 victory over Halifax in the 1989–90 Regal Trophy Final during the 1988–89 season at Headingley, Leeds on Saturday 13 January 1990,[15] and played at centre in the 15–8 victory over Bradford Northern in the 1992–93 Regal Trophy Final during the 1992–93 season at Elland Road, Leeds on Saturday 23 January 1993.

[16] During the 1992–93 Rugby Football League season Bell played at centre for defending RFL champions Wigan in the 1992 World Club Challenge against the visiting Brisbane Broncos.

In 1994 Bell left Wigan, returning home to join coach John Monie at the new Auckland Warriors club.

In his début match he played alongside his uncle Ian Bell, and his cousin Clayton Friend.

During the 2000 World Cup he was the assistant Coach of the Aotearoa Māori side, working under his dad Cameron Bell.