Kathog Monastery is located above Pakyong Bazaar, East Sikkim. The lineage holders of Saint Kathog Kuntu Zangpo founded it in 1840 A.D. Kathog Lama was one of the three pioneer Lamas who played a part in coronation of Phuntshog Namgyal as the first King of Sikkim in 1642 A.D. at Yuksam, West Sikkim. It is said that Kathok Lama, during his time, founded only one small Shrine known as ‘Kathok Lhakhang’ at Yuksam in 1643 A.D.

 Later on, due to the damage during the Gorkha war and frequent war tension, his lineage holders moved their Religious Centre to present place. The department of Ecclesiastical Affairs extended a marginal financial assistance for restoration works as the structure was damaged by earthquake in 1980. Later, the Lamas and devotees moved the demand for reconstruction in 1982. Due to fund constraints of the department, the proposal was forwarded to Culture department and funding from this department helped rebuild the monastery in 1990.
     Some of the main artifacts are:

i.	A Conch Shell:It is said that this conch shell came flying from West direction and landed here.
ii.	A foot long key: This key is said to be the key to open the treasure of mount Khangchen Dzonga.
iii.	A Small Tibetran Shoe: It is said to belong to a highly accomplished lama by the name Gyalwa Yeshey Phungpa.
iv.	A Metal Vajra: Blessd by Guru Padmasambhava.

      Presently the Gonpa has 40 monks and 35 novice monks.It follows Nyingma Kathokpa of Tibetan Buddhism. Presently, it is one of the major monasteries in East Sikkim and functions all the major ceremonies with mask dance.