Pa Sang (Thai: ป่าซาง, pronounced [pàː sāːŋ]) is a district (amphoe) of Lamphun province, northern Thailand.

Neighboring districts are (from the east clockwise) Mueang Lamphun, Mae Tha, Ban Hong and Wiang Nong Long of Lamphun Province, Doi Lo and San Pa Tong of Chiang Mai province.

Originally named Pak Bong after its central sub-district, the district was renamed Pa Sang in 1953.

They migrated from Muang Yong of Shan State of today's Myanmar to the northern part of Thailand in 1805 or in the early-Rattanakosin period.

[2] Pa Sang district is divided into nine sub-districts (tambons), which are further subdivided into 90 administrative villages (mubans).