Small prolin-rich proteins (Sprrs) participate in the construction of cornified cell envelop in stratified squamous epithelial cell. Their functions in the simple epithelium are not clear. Northern blots and semi-quantitative RT-PCR were used to investigate the expression pattern of Sprr2 in mice uteri during the estrous cycle and pregnancy as well as their hormonal regulation. The results showed the up-regulation of Sprr2 in the proestrous and estrous uteri during the estrous cycle. The expression of Sprr2 was rapidly down-regulated at the early stage of pregnancy until the perinatal stage when it was re-induced and reached the high level after labor. Due to its unique expression pattern in the uterus at different reproductive stages and its protective function in stratified squamous epithelial cell, its role in uteri against reproductive stress such as copulation and labor was suggested.