Our results reveal the difference in the expression patterns of MMPs and TIMPs during follicle development between normal and miniature pigs. MMP-9 was highly expressed in the Graafian follicles of normal pigs, whereas in miniature pigs, its levels during the follicular stage were lower than that in normal pigs. However, during the developing stages, MMP-2 expression was higher in miniature pigs than in normal pigs. TIMP-2 expression was low in both breeds, but TIMP-3 levels were higher in miniature pigs than in normal pigs. Together, these results indicate that MMP expression can be used as an indicator of developmental changes in porcine follicular cells. Based on MMP and TIMP expression profiles, we believe that MMPs play an important role in follicular development by regulating the remodelling of porcine follicular cells.