Gossaigaon is a town in Kokrajhar district of the northeastern state of India, Assam. It is located between 26.45° North latitude and 89.97° East longitude at an average elevation of 50 metres (164 feet) above mean sea level. The town is also the headquarters of the Gossaigaon sub-division. At 2 km from the town is the railway station and the airport is at Borjhar. The NH 31, which passes through Gossaigaon, connects it with the other places in the state. The Gongia River, also known as Tipkai, flows through the border of the town.

Just 5 km from the town, Guwabari Silkworm Rearing Center, produces large quantities of silkworm cocoons. Agriculture is the main occupation of the people.

As per the 2001 census report, Gossaigaon had a population of 13,267. Males and females constitute 53% and 47% of the population. In Gossaigaon, 13% of the population is less than six years of age. The average literacy rate of this town is 76%, which is much higher than the national average literacy rate of 59.5%. The literacy rate of the male is 82% and the female literacy rate is 68%.