Bitter Lake is a small lake and neighborhood in north central Seattle, Washington.

The lake covers 19 acres, with a mean depth of 16 feet and a maximum depth of 31 feet. Until 1913, a sawmill was located at its southwest corner. Tannic acid from logs dumped into the lake gave its water a bitter taste and the lake itself a name. The Seattle-to-Everett Interurban trolley reached the lake in 1906, and the neighborhood was annexed by Seattle in 1954.

The lake itself is situated between Greenwood Avenue N. to the west, Linden Avenue N. to the east, N. 137th Street to the north, and N. 130th Street to the south, which streets form the generally accepted boundaries of the neighborhood, though some extend the eastern boundary one block east to Aurora Avenue N.