The 2005–06 Northern Premier League season was the 38th in the history of the Northern Premier League, a football competition in England. Teams were divided into two divisions; the Premier and the First.

Premier Division

The Premier Division featured six new clubs:

League table

Results

Play-offs

The Premier Division playoffs saw the second to fifth placed sides in the Division compete for one place in the Conference North.

• After extra time

Division One

Division One featured four new clubs:

League table

Results

Play-offs

The First Division playoffs saw the third to sixth placed sides in the First Division compete for a place in the Premier Division.

Promotion and relegation

In the thirty-eighth season of the Northern Premier League Blyth Spartans (as champions) and Farsley Celtic (as play-off winners) were promoted to the Conference North. Wakefield, Bradford Park Avenue and Runcorn Halton were relegated to the First Division; these three clubs were replaced by relegated Conference North side Hednesford Town, First Division winners Mossley, second placed Fleetwood Town and play-off winners Kendal Town. In the First Division Bishop Auckland were relegated and were replaced by Buxton, Cammell Laird, Harrogate Railway Athletic, Alsager Town and Skelmersdale United.

Cup Results

Challenge Cup: Teams from both leagues. President's Cup: 'Plate' competition for losing teams in the NPL Cup. Chairman's Cup: 'Plate' competition for losing teams in the NPL Cup. Peter Swales Shield: Between Champions of NPL Premier Division and Winners of the NPL Cup.