An Cu is a plain commune along O Loan lagoon, 5,4km south of Tuy An district center. To the east it borders An Hoa Hai and An Ninh Dong commune;to the west it borders Chi Thanh town, to the south it border An Hiep commune; to the north it borders An Thach  commune and Chi Thanh town. With a natural area of 2.089,38 hectares, the agricultural land area is 1.465,63ha; non- agricultural land is 619.40ha and unused land is 4.34ha.(aquaculture water surface area: 130,63 ha) The whole commune has a total of 3,268 households, with 10,365 people  distributed in 5 villages ( Phu Tan 1, Phu Tan 2, Hoa Thanh, Tan Long and Phuoc Luong). The majority of people live on agriculture, the remaining 80% are in other occupation.