| Competition: | Welsh Alliance League |
| Season: | 2005–06 |
| Winners: | Prestatyn Town |
| Relegated: | Cemaes Bay and Penmaenmawr Phoenix |
| Matches: | 240 |
| Total Goals: | 990 |
| Prevseason: | 2004–05 |
| Nextseason: | 2006–07 |
| Updated: | 24 February 2019 |
The 2005–06 Welsh Alliance League is the 22nd season of the Welsh Alliance League, which is in the third level of the Welsh football pyramid.
The league consists of sixteen teams and concluded with Prestatyn Town as champions and promoted to the Cymru Alliance. Cemaes Bay were relegated to the Gwynedd League and Penmaenmawr Phoenix were relegated to the Clwyd League.
Bodedern Athletic were champions in the previous season. They were replaced by Cemaes Bay who were relegated from the Cymru Alliance and Nefyn United who were promoted from the Gwynedd League.
| Team | Location | Ground | |
|---|---|---|---|
| Parc Meurig | |||
| Lon yr Ysgol | |||
| School Lane | |||
| Y Morfa Stadium | |||
| Central Park. | |||
| Cae Ffwt | |||
| Ffordd Padarn | |||
| Arriva Ground | |||
| Eithin Duon | |||
| Gwydir Park | |||
| Cae'r Delyn | |||
| Penmaenmawr Phoenix | Cae Sling | ||
| Bastion Road | |||
| Dolfechlas Road | |||
| Rhyl Reserves | Belle Vue | ||
| Sealand Rovers |