Kongchogsaum Lhakhang, Tibetan Buddhist monastery in Bumthang, Bhutan.

Könchogsum Lhakhang, also called Tsilung, is a Nyingma monastery in Bumthang, eastern Bhutan, about 300 m south of Tamshing Lhakhang. Its main sanctuary holds a statue of Vairocana, statues of Padmasambhava and Avalokiteśvara, and paintings of Pema Lingpa and Longchenpa. A stone in the courtyard is said to have sealed the entrance to a lake behind the monastery. The temple was rebuilt after a February 2010 fire and consecrated in November 2014.

Padmasambhava is said to have hidden texts at this site in the 8th century; the tertön Bonpo Dragtshel found them as a terma in 1039. A butter lamp that fell over started a fire on 25 February 2010 that badly damaged the monastery. The rebuilt temple and monastery were consecrated in November 2014.

The temple is also called Tsilung and belongs to the Nyingma school, one of Bhutan's four main Buddhist schools. Its paintings are attributed to Longchenpa, author of the Seven Treasuries, and to Pema Lingpa, held to be an incarnation of Longchenpa. A stone in the courtyard is said to have sealed the entrance to a lake behind the monastery.

Könchogsum Lhakhang stands about 300 m south of Tamshing Lhakhang in Bumthang, so the two are easily visited on foot in one outing. The stone said to have sealed the lake's entrance now lies in the monastery courtyard and is worth looking for. The temple was rebuilt after the February 2010 fire and consecrated in November 2014.

The stone that once sealed the entrance to the lake behind the monastery is said to still stand in the courtyard. Pema Lingpa is credited with finding the hidden lake, and the blocked passage is pointed out to visitors.