Objective To investigate the effects and ascertain the significance of microwave radiation on the expression of phosphorylated cyclic adenosine monophosphate (cAMP)-response element-binding protein (pCREB), cAMP-responsive element modulator (CREM), and CREB-binding protein (CBP) in the testicular tissue of rats. Methods Thirty male Wistar rats were randomly divided into control group (n=5) and radiation group (n=25). Five rats in the radiation group were sacrificed at 6h, 1, 3, 7, and 14d, respectively, after exposure to microwave radiation for 5min, with an average power density of 30mW/cm2. Rats in the control group were sacrificed within 1d without receiving microwave radiation. Expressions and dynamic changes in pCREB, CREM, and CBP in the testicular tissues were examined by immunohistochemistry and Western blotting. Results pCREB, CREM, and CBP were mainly expressed in the sperm nuclei of the seminiferous tubule in the rat testis. pCREB and CBP protein expressions were downregulated from 6h to14d (except for pCREB at 1d) after exposure to microwave radiation (P < 0.05 or P < 0.01). The expression of CREM was also weakened significantly from 6h to 7d after radiation (P < 0.05 or P < 0.01). Conclusion The downregulation of pCREB, CREM, and CBP expression may play an important role in the injury of spermatogenic cells caused by microwave radiation.