It occupies the province's easternmost part, in the Dong Phaya Yen Mountains which divide the central and northeastern regions.

[1] The forests of Dong Phaya Yen were rapidly cleared following the construction of Mittraphap Road in 1955, which vastly opened up access to the area.

The district lies in the hills of the Dong Phaya Yen Mountains, which separate central Thailand from the northeastern region (Isan).

The Chet Sao Noi Waterfalls lie downstream to the north, and the eponymous national park covers forested hill areas in the vicinity.

The under-construction (as of 2022) Motorway 6, with an access ramp serving Muak Lek, is expected to supplant Mittraphap as the most direct route from Bangkok to Nakhon Ratchasima.

As Khlong Muak Lek forms a valley between the surrounding hills, the original railway was forced to snake through the area in a large U shape as it passed the town to the east.

As part of infrastructure work to upgrade the railway to double-track from 2016 to 2024, a 50-metre (160 ft)-high viaduct—the first of its kind in Thailand—was built to cross over the valley and the town altogether.