Ashby is a city in Grant County, Minnesota, United States. The population was 446 at the 2010 census.
According to the United States Census Bureau, the city has a total area of 0.6 square miles (1.5 km²), of which, 0.5 square miles (1.4 km²) of it is land and 0.04 square miles (0.1 km²) of it (7.02%) is water.
Minnesota State Highway 78 serves as a main route in the community. Interstate 94 is nearby.