Gyaisi County contains 9 towns, 4 townships, and 3 ethnic townships: Due to its elevation, Jiulong County has a subtropical highland climate (Köppen Cwb), with strong monsoonal influences; winters are frosty and summers warm with frequent rain.

The monthly 24-hour average temperature ranges from 1.6 °C (34.9 °F) in December and January to 15.3 °C (59.5 °F) in July, while the annual mean is 9.1 °C (48.4 °F).

Over 75% of the annual precipitation of 922.5 mm (36.3 in) occurs from June through September.

With monthly average percentage of sunny days ranging from 32% in July to 58% in January, the county seat receives 1,983 hours of bright sunshine annually.

Diurnal temperature variation is large, averaging 14.2 °C (25.6 °F) annually.