Lamduan (Thai: ลำดวน, pronounced [lām.dūa̯n]) is a district (amphoe) in the central part of Surin province, northeastern Thailand.

The district dates back to the Mueang Suraphinthanikhom (สุรพินทนิคม), which was established in 1871.

On 3 January 1977 it was reestablished as a minor district (king amphoe) by splitting off the two tambons, Lamduan and Chok Nuea, from Sangkha district.

[2] Neighboring districts are (from the north clockwise): Sikhoraphum, Si Narong, Sangkha, Prasat and Mueang Surin.

The district is divided into five sub-districts (tambons), which are further subdivided into 51 villages (mubans).