Sa Kaeo is 245 kilometres, east of Bangkok, with the area about 7,195 square kilometres. Sa Kaeo is divided into 7 Amphoes (districts) and 2 King Amphoe (sub-districts): Amphoe Muang, Amphoe Watthana Nakhon, Amphoe Aranyaprathet, Amphoe Ta Phraya, Amphoe Khao Chakan, Amphoe Wang Nam Yen, Amphoe Khlong Hat, King Amphoe Khok Sung, and King Amphoe Wang Somboon.

Sa Kaeo has its border facing Cambodia of approximately 165 kilometres. Generally, the area varies from plains to highlands.

Highlands and mountains are in the north where Pang Sida National Park is located, while the south is covered with wavy plains and hills. Also, there are evergreen forests along the Chanthaburi mountain range. In the central, there are plains and hills, with Amphoe Watthana Nakhon as the highest area when compared to the other Amphoe Mueang in the west, and Amphoe Aranyaprathet in the east.

The north of the province is covered with the forested mountains of the Dong Phaya Yen range. To the south are foothill plains, which are mostly deforested.

Two national parks are located in the Cardamom Mountains at the border to Cambodia, protecting the rain forests.

In the past, Sa Kaeo was a major civilized community. Its long history had dated back since the Suwannaphum and Dvaravati Periods. The archeological sites of Khmer arts and stone inscriptions are the outstanding examples of this civilization.