Zanjira Upazila (Shariatpur Sadar district) with an area of 239.53 sq km, is surrounded by Lohajang and Songbari upazilas on the north,Shariatpur Sadar and Naria upazilas on the south, Naria upazila on the east, Shibchar and Madaripur Sadar upazilas on the west. 

Main rivers are Padma and Palang. 

Zanjira (Town) consists of 9 wards and 19 mahalllas. The area of the town is 1.32 sq km. It has a population of 16896; male 48.99%, female 51.01%. The density of population is 12800 per sq km. The literacy rate among the town people is 39.9%. 

Administration Zanjira thana was established in 1973 and was turned into an upazila in1984. It consists of 12 union parishads, 126 mouzas and 179 villages. Population 157316; male 51.13 %, female 48.87%; Muslim 98.90%, Hindu 0.98% and others 0.12%. 

Religions institutions Mosque 508. 

Literacy and educational institutions Average literacy 18.02%; male 24.8% and female 11.3%. 

Educational institutions: college 3, high school 10, government primary school 56, non-government primary school 36, madrasa 8. Cultural organisations Rural club 23. 

Main occupations Agriculture 63.7%, agricultural labourer 19.23%, wage labourer 2.12%, commerce 6.06%, service 2.18%, others 6.71%. 

Land control Among the peasants, 45.47% are landless, 4.54% rich, 18.18% intermediate and small 31.81%.

Value of land Market Value of first grade land is Tk 7000 per 0.01 hectare. 

Main crops Paddy, Jute, wheat, tomato, brinjal, garlic, onion and kalijira. Extinct and nearly extinct crops Kaun, sesame, hemp jute and methi. 

Main fruits Mango, wood-apple, blackberry, banana and coconut. Fisheries, dairies and poultries Dairy 23, poultry 241. 

Communication facilities Roads: pucca 7.01 km, semi pucca 18.07 and mud road 456.67 km. 

Traditional transport Palanquin (extinct), boat, Gaina boat (nearly extinct). Manufactories Saw mill 6, oil mill 6 and welding 4. 

Cottage industries Blacksmith 17, goldsmith 28, potteries 12, bamboo work 9. 

Hats, bazrs and fairs Hats and bazars are 16, most noted of which are Kazir hat and Laukhola hat. 

Main exports Tomato, onion, garlic and kalijira. 

NGO activities Brac,Proshika, Grameen Bank,ASA, SDS, UST and Maripur Legal Aid Association. 

Health centre Upazila health complex 1 and satellite clinic 3