Santo Tomás Jalieza is a town and municipality in Oaxaca in south-western Mexico.

[1] The municipality covers an area of 51.03 km2 at en elevation of 1,500 meters above sea level.

The soil is composed of volcanic material overlaying rock at a depth of 10 centimeters or less.

[1] As of 2005, the municipality had 568 households with a total population of 2,885 of whom 382 people spoke an indigenous language.

Economic activity includes agriculture, producing maize, beans, wheat, sugarcane and fruits, and cattle rearing.