Rajapur and Bhandaria upazilas on the north, Bamna and Betagi upazilas on the south, Betagi upazila on the east, Bhandaria and Mathbaria upazilas on the west.

Kathalia thana was established in 1930 and was turned into an upazila in 1983. It consists of 6 union parishads, 47 mouzas and 52 villages.

Kathalia Upazila is located in Jhalokati District. Upazilla(s)/Thana(s) in Jhalokati are Jhalokati Sadar Upazila, Kathalia Upazila, Nalchity Upazila, Rajapur Upazila.