Chong Nonsi is a sub-district (khwaeng) located in the Yan Nawa District of Bangkok, Thailand. Situated along the banks of the Chao Phraya River, it constitutes one of the two primary sub-districts within the district.
As of late 2018, Chong Nonsi covered a total area of 9.984 square kilometers and had a population of approximately 48,277 people. The area is divided into 13 communities and serves as the location for the Yan Nawa District Office.