Bhimtal Lake, Mountain lake in Kumaon region, India.

Bhimtal Lake is a C-shaped lake in Bhimtal town, Nainital district, Uttarakhand, at 1,375 m elevation. Its 1883 masonry dam, 150 m long and 14.8 m high, impounds 47.8 hectares with a gross storage of 4.63 million cubic metres. A peripheral road runs along the banks, and a small island in the centre holds an aquarium reached by rowing boat.

A masonry dam was built in 1883 during the British Raj period to store water for local supply. This structure fundamentally changed the area and created a vital water storage resource for the region.

The lake and town are named after Bhima, one of the Pandavas in the Mahabharata, who is said to have visited the site. Near the dam stands a temple built in the 17th century by Raja Baj Bahadur Chand of the Kumaon Kingdom. A local myth holds that the lake's water turns brown in some months and clears only after the lake claims a victim.

The lake lies 22.5 km from Nainital and 20 km from Kathgodam, the nearest railhead. A peripheral road along the banks gives views of fish in the water, and rowing boats reach the island aquarium. The dam holds 12 flood gates and releases water to the Gola River, which can lower the surface by 11 metres.

The lake's water turns brown in some months because of tiny organisms called animalcules. A local belief holds that the colour clears once the lake takes a life. The reservoir is also classed as manomictic, mixing fully only once a year.