Tuanshan is a city in Liaoning Province in northeastern China. It is located in the southern part of the province, within the administrative area of Yingkou, a prefecture-level city on the coast of the Bohai Sea. The town lies on the Liaodong Peninsula, a region characterised by a continental climate with cold, dry winters and warm, humid summers.
Historically, Tuanshan is best known as a former trading and administrative centre in the Liaodong region. Its position near the coast and along routes linking the interior of Liaoning with the ports of the Bohai Sea gave it a role in local commerce and transport. The surrounding area is predominantly agricultural, with farming and fishing forming the traditional economic base of the communities in the district.
Today Tuanshan is a small urban settlement rather than a major city, and it functions largely as a local service centre for the surrounding rural townships. It is connected by road to Yingkou and to the wider transport network of Liaoning Province. The town is not a prominent tourist destination, and its significance is chiefly local and regional within the broader context of northeastern China.