Cullison is a city in Pratt County, Kansas, United States. As of the 2020 census, the population of the city was 83. Cullison was a station and …Cullison is a city in Pratt County, Kansas, United States. As of the 2020 census, the population of the city was 83. Cullison was a station and shipping point on the Chicago, Rock Island and Pacific Railroad. Cullison was named for John B. and Mary M. Cullison, original owners of the town site.