Cangnan County is located on the southernmost coast of Zhejiang Province, adjacent to the East China Sea and separated by sea from Taiwan. It is under the jurisdiction of Wenzhou City in Zhejiang. The county government sits in Renmin Avenue of Lingxi Town. It has once been under Pingyang County's jurisdiction and was designated as an independent county in 1981.

The county's name Cangnan is derived from its location in the south of Yucang Mountain. Situated at 120°23'E and 27°30'N, Cangnan is often referred to as the "Southern Gateway of Zhejiang" and enjoys a subtropical maritime monsoon climate, with mild winters and cool summers. The county is rich in natural resources, with abundant specialties such as aquatic products, minerals, and tourism resources. It is known for its four-season pomelos, sweet oranges and tea, which have significant development prospects. Notably, the county boasts a rare 1,800-meter-long Yuliao Beach, a sandy coastal stretch rarely seen on the Chinese mainland.

Cangnan County's urban area is 81 km from Wenzhou's city center, 432 km from the provincial capital Hangzhou, with National Highway 104 traversing the area from north to south. It is promising with advantageous geographical location and transport conditions.