Annealing of (CdZn)Te substrate material is an important technology to enhance the quality of HgCdTe epitaxial material as well as the performance of infrared focal plane array detectors. In this paper, the size variations of inclusions defects in (CdZn)Te material after annealing were investigated. And the quantitative dependencies of the inclusion defect sizes on the sample temperature, Cd partial pressure and annealing time were obtained. Some properties of inclusion defects and rules of inclusion defect evolution in annealing were revealed. The models of the inclusion defects and the physical mechanism of annealing process based on atom diffusions were proposed to describe the experimental results. The research results can help us to better understand the evolution process of the inclusion defects in annealing and find suitable annealing technology to obtain high-quality (CdZn)Te materials. (C) 2016 Elsevier B.V. All rights reserved.