Lake Beechey (sometimes Beechey Lake) is a lake in Kitikmeot, Nunavut, Canada. It is a long, narrow, lake-expansion of the Back River. It is part of the western Canadian Precambrian Shield. It contains a few unnamed islands. Historically, Lake Beechey was the southernmost territory of Copper Inuit. The lake was discovered by explorer George Back and named by Sir John Franklin in honor of Frederick William Beechey.