Samut Prakan, also known as Paknam is located at the mouth of the Chao Phraya River and neighboring with provinces such as Bangkok in the north and Chachoengsao to the east.The town is only 25 kms south of Bangkok and easily frequented by bus. Its old community settled in Phra Pradaeng (now a northern district) during the Ayutthaya Period. The modern town and several fortresses, were built by the command of King Rama II in 1819. Samut Prakan occupies an area of 1,004 square kilometres.
Bangkok New International Airport or also called Suvarnabhumi Airport is located in this province.