As the demand for construction materials, especially bricks, increases, efforts are needed to improve product quality to meet strength and durability standards. This study aims to analyze the effect of the addition of zeolite as an additive in clay soil on the compressive strength of post-firing bricks. The variations of zeolite addition used are 0%, 5%, 10%, 15%, 20%, and 25%. Testing includes soil characteristics, shrinkage, and compressive strength of bricks at 3, 7, and 14 days of age. The results of the study show that the addition of zeolite is able to improve the mechanical properties of bricks, especially in reducing burn shrinkage and increasing compressive strength. The minimum burn shrinkage value was achieved at the addition of 25% zeolite of 21.4%, while the optimum compressive strength value of 55.97 kg/cm² was obtained at the 25% zeolite variation with a residence time of 5 days and a test life of 14 days. Thus, the addition of zeolite can be an effective alternative in improving the quality of bricks to support construction needs.