*All wins for Penn State (11-1, 7-1) vacated due to scandal. Rankings from AP Poll / Coaches' Poll
The 2005 Purdue Boilermakers football team represented Purdue University during the 2005 NCAA Division I-A football season. The team was coached by Joe Tiller and played its home games at Ross–Ade Stadium. Purdue played eleven games in the 2005 season, finishing with a 5–6 record and missing a post-season bowl game for the first time since 1996. Purdue was predicted by many as a dark horse for the Big Ten title, but after a strong 2–0 start, lost six straight before rebounding to finish a more respectable 5–6.