The history of Lom Sak area dates back to the founding of the Sukhothai Kingdom in the 13th century.

According to the historian Prince Damrong Rajanubhab, Mueang Lom Sak was established in the reign of King Nangklao (Rama III).

Nam Nao National Park protects some of the hills of the district.

Khao Kho National Park is currently being developed and will also occupy parts of the district.

The district is divided into 23 sub-districts (tambons), which are further subdivided into 251 villages (mubans).