2005 Northern Arizona Lumberjacks football team

The 2005 Northern Arizona Lumberjacks football team was an American football team that represented Northern Arizona University (NAU) as a member of the Big Sky Conference (Big Sky) during the 2005 NCAA Division I FCS football season. In their eighth year under head coach Jerome Souers, the Lumberjacks compiled a 3–8 record (1–7 against conference opponents), were outscored by a total of 338 to 233, and finished in a tie for last place in the Big Sky.

The team played its home games at the J. Lawrence Walkup Skydome, commonly known as the Walkup Skydome, in Flagstaff, Arizona.