Walsden (/ˈwɒlzdən/; WOLZ-dən) is a large village in the civil parish of Todmorden in the Metropolitan Borough of Calderdale, West Yorkshire, England.

It was historically partially administered in Lancashire (the Walsden Water as tributary to the Calder serving as the county boundary), and close to the modern boundary with Greater Manchester. It lies along the A6033 Keighley to Littleborough road in the Walsden Valley, a branch of the Upper Calder Valley, and is 2 miles (3.2 km) south of Todmorden and 4 miles (6.4 km) north of Littleborough.

Walsden railway station, on the Leeds—Todmorden—Manchester line, originally opened in 1841 and re-opened 10 September 1990, having been closed for almost 30 years.

The canal and A6033 between the former Bird in'th Hand pub and the Bellholme football pitches was also the only place to be bombed in Todmorden during the Blitz; the blasts breached the Rochdale Canal and broke a water main on Rochdale Road.

Multiple small craters can still be picked out on both hillsides, one of which contains the Summit Tunnel trans-Pennine railway line, which may have been an alternative target for a raid primarily aimed at the Manchester area; its easterly Yorkshire end is less than ¼ mile away.

The road was quickly repaired, the canal was shored up with earth from the former floodplain of Walsden Water (which is why the pitches are above the natural ground level) and the whole bombing incident was hushed up.

Walsden was originally administered by Rochdale corporation in the county palatine of Lancashire, hence some of the local historical archives are held by Rochdale MBC.

The village sits wholly within West Yorkshire with boundaries to Greater Manchester (south by southwest) and Lancashire (west by northwest)