Kotayk province is located at the central part of Armenia, and occupies the northeastern part of the Ararat plain. The Kotayk plain located between Hrazdan and Azat rivers has a height of 1200–1500 meters above sea level. It is dominated by the Gegham mountains from the northeast including the mountains of Azhdahak, Hatis and Gutanasar. The province approximates the Pambak mountains at the north, while the Tsaghkunyats mountains lie at the west, and the Voghjaberd mountains at the southwest of Kotayk. Affected by the Gegham volcanoes, the land relief of Kotayk is covered with lava and tufa.
Hrazdan, Getar and Azat are the three major rivers of the province. Lake Akna located at a height of 3032 meters, is the only lake in the province.
The climate of the province is quite diversified. It ranges between arid and semi-arid climate at the south, and snowy climate at the center and the north. Annual precipitation levels are less than 200 mm at the dry areas, and they range between 400 and 900 mm at the higher elevations in the center and the north of the province.
The wildlife sanctuaries of the province are formed to protect the relict mountain forest and meadow ecosystems, and include such species as Corn Crake and Grasshopper Warbler, as well as community of wild Orchids, and the Litvinov's Birch tree.