Tatlayoko Lake is a lake on the Homathko River in the western Chilcotin District of the Central Interior of British Columbia, Canada, located on a north-south axis just upstream of the entrance of the series of canyons of the Homathko, including the Great Canyon of the Homathko, on its route to the sea at the head of Bute Inlet. The community of Tatlayoko Lake, British Columbia is located at its northern end.