The province borders Zamboanga del Norte to the north, Zamboanga Sibugay to the west, Misamis Occidental to the northeast, and Lanao del Norte to the east. To the south is the Moro Gulf. Zamboanga del Sur occupies the southern section of the Zamboanga peninsula that forms the western part of the Island of Mindanao. It is located at longitude 122° 30"" and latitude 7° 15"" north. It has a total land area of 473,491 hectares or 4,734.91 square miles.
Zamboanga del Sur is subdivided into 26 municipalities and 1 city. These divisions are further subdivided into 681 barangays. The province comprises two congressional districts. Pagadian City is the capital.
The most commonly spoken language is Bisaya. Also spoken, although in small percentage, are Zamboangueño, Tagalog, English, Hiligaynon, Maguindanao, Iranun, Subanen, and Ilocano.
As of the 2010 census, Zamboanga del Sur has a population of 959,685, making it the 16th most populous province. The population density is 3,480/km², the 20th most densely populated province.
The Zamboanga del Sur Police Provincial Office logo is circular in form with green stripe around the edge with the official markings in bold letters ZAMBOANGA DEL SUR POLICE PROVINCIAL OFFICE in blue with white background.
The three yellow golden stars represent the three Congressional Districts of the province. (However, the 3rd Congressional District had been created into one province known as Zamboanga Sibugay). The inner circle with a yellow background with the shield and green leaves below the shield symbolizes the following:
The shield represents protection;
The green leaves represent peace;
1952 is the year the province was established;
The golden crescent with small star in orange background at the upper left side of the shield symbolizes the Muslim populace of the province and the white cross at the upper right side of the shield symbolizes the Christians, both living in harmony with each other;
The clouds, mountains, valleys and green fields represent the agricultural industry of the province;
The ocean and green vinta with white sail represent the fishing industry of the province; and
The roman numeral IX in the white sail represents Region 9 where the province belongs.
Zamboanga del Sur PPO was then named as Zamboanga del Sur Philippine Constabulary Command. It is situated in Camp Abelon, Pagadian City. The defunct PC/INP Command previously covered three congressional districts. Later on, the 3rd District was made into one province named as Zamboanga Sibugay, while the two other congressional districts remained under the operational jurisdiction of this police provincial office.