According to the United States Census Bureau, the town has a total area of 10.0 square miles (26 km2).

There were 159 housing units at an average density of 15.9 per square mile (6.1/km2), of which 1 (100%) were owner-occupied, and 0 (0%) were occupied by renters.

Little Grass Valley was initially occupied by the Maidu Native American tribe during the summers.

The land in the valley was used to graze cattle and there was a Boy Scout Camp located on the banks of the South Fork of the Feather River.

Today there are campgrounds all around the lake, cabins on the south side, and it is the center of a snowmobiling area.

[7] Federally, Little Grass Valley is in California's 1st congressional district, represented by Republican Doug LaMalfa.