Betagi, Mirzaganj and Patuakhali Sadar upazilas on the north, the bishkhali river and Patharghata and Bamna upazilas on the west, the burishwar river and Amtali upazila on the east and the bay of bengal on the south.

Barguna Sadar thana was turned into an upazila in 1982. The upazila consists of one municipality, 13 union parishads, 62 mouzas and 189 villages.

Barguna Sadar Upazila is located in Barguna District. Upazilla(s)/Thana(s) in Barguna are Amtali Upazila, Bamna Upazila, Barguna Sadar Upazila, Betagi Upazila, Patharghata Upazila.