| Jean-Marie Cadieu | |
| Birth Place: | Tulle, France |
| Weight: | 102kg (225lb) |
| Position: | Lock |
| Repteam1: | France |
| Repyears1: | 1991-1992 |
| Repcaps1: | 12 |
| Reppoints1: | 4 |
| Amatyears1: | 1982-1993 |
| Amatyears2: | 1993-1995 |
| Amatteam1: | Stade Toulousain |
| Amatteam2: | RC Narbonne |
| Years1: | 1995-2006 |
| Clubs1: | RC Narbonne |
| Birth Date: | 16 October 1963 |
Jean-Marie Cadieu (born 16 October 1963 in Tulle) is a former French rugby union player. He played as a lock.
Cadieu played for Stade Toulousain from 1982/83 to 1992/93, where he won 3 titles of the French Championship, in 1984/85, 1985/86 and 1988/89, and a Cup of France, in 1983/84. He then moved to RC Narbonne, where he developed from 1993/94 to 2005/06, when he finished his career.
Cadieu had 12 caps for France, from 1991 to 1992, scoring 1 try, 4 points in aggregate. He played 4 games at the 1991 Rugby World Cup. He had 2 matches at the Five Nations Championship in 1992.