Stanley is a rural municipality (RM) in the province of Manitoba in Western Canada.

Since 1876, the area made up part of the Mennonite West Reserve.

The municipality is named for The Lord Stanley of Preston, 16th Earl of Derby, Governor General of Canada from 1888 to 1893, namesake for the Stanley Cup, which he donated.

According to Statistics Canada, the RM has an area of 835.59 km2 (322.62 sq mi).

This does not include the areas belonging to the cities of Winkler and Morden, which are surrounded by the RM, in its north-eastern and northern sections, respectively.