In the study, we found that expressions of ERK1/2 and p-ERK1/2 were both positive correlated with the expression of BKCa in 185 cases with type I endometrial cancer, and BKCa could regulate the expression of p-MEK1/2 and p-ERK1/2 to influence cell growth and invasion in endometrial cancer cells. The gene discussed is MAPK3; the disease is endometrial cancer.