Rock Lake was a provincial electoral district of Manitoba, Canada.
The constituency was created by redistribution in 1956, and existed from the 1958 provincial election until the 1981 election. Most of the area was merged into the constituency of Pembina.
It was located in the southern part of the province. It was bordered to the north by Souris-Lansdowne, to the east by Pembina, to the west by Turtle Mountain, and to the south by the American state of North Dakota.
Source: Elections Manitoba
1958:
1959:
1962:
1966:
1969:
1973:
1977: