Objective To investigate and analyze the expression and cellular function of glutathione S transferase P1 (GSTP1) and Ras guanylnueleotide releasing proteins 1 (RasGRP1) in breast cancer and their effects on the proliferation and migration of MCF-7 cells. Methods The breast cancer tissues and corresponding adjacent tissues of 80 newly diagnosed patients were collected. The expression of GSTP1 and RasGRP1 was detected by immunohistochemistry. And the expression of GSTP1 and RasGRP1 with pathological factors was analyzed. The inhibition expression of GSTP1 and RasGRP1 in MCF-7 cells were prepared by transfection. The proliferation and cell migration of MCF-7 cells were detected. The expression of GSTP1 and RasGRP1 protein in different MCF-7 cell groups was detected by Western blotting. Results Compared with the adjacent tissues, the positive rate of GSTP1 in breast cancer tissue had increased (P < 0.05), and the positive rate of RasGRP1 had decreased (P < 0.05). GSTP1 had increased in patients with lymph node metastasis, while RasGRP1 had decreased (P < 0.05). With the development of TNM stage, the GSTP1 increased , and RasGRP1 decreased (P < 0.05). The inhibition rate of MCF- 7 cells at 12 h, 24 h, and 48 h in the control group 1, negative control group 1, and the GSTP1-siRNA group, were respectively different (P < 0.05). Furthermore, the significant differences exited among three groups (P < 0.05). The change trend in the GSTP1-siRNA group was higher than the control group 1 and the negative control group 1 (P < 0.05), while the differences of change trend also emerged between each two group. The inhibition rates of MCF-7 cells in the control group 2, the negative control group 2, and the RasGRP1-siRNA group at 12 h, 24 h, and 48 h showed: the inhibition rates at different time points were different (P < 0.05); the inhibition rates between each two groups were different (P < 0.05); The change trend between each two groups were different (P < 0.05). The number of permeable cells in the control group 1, the negative control group 1, and the GSTP1-siRNA group was statistically significant (P < 0.05). Compared with the control group 1 and the negative control group 1, the number of permeable cells in the GSTP1-siRNA group had decreased (P < 0.05). The number of permeable cells of MCF-7 cells in the control group 2, the negative control group 2, and the RasGRP1-siRNA group, was statistically significant (P < 0.05). Compared with control group 2 and the negative control group 2, the number of permeable cells of MCF-7 cells in the RasGRP1-siRNA group had increased (P < 0.05). The relative expression of GSTP1 protein in the control group 1, negative control group 1, and GSTP1-siRNA group were statistically significant (P < 0.05). Compared with the control group 1 and the negative control group 1, the relative expression of GSTP1 protein in the GSTP1-siRNA group had decreased (P < 0.05). The relative expression of RasGRP1 protein in the control group 2, the negative control group 2 and the RasGRP1-siRNA group were statistically significant (P < 0.05). The relative expression of RasGRP1 protein in the RasGRP1-siRNA group was lower than the control group 2 and the negative control group 2 (P < 0.05). Conclusions Both GSTP1 and RasGRP1 proteins are abnormally expressed in breast cancer, which can affect the proliferation and migration ability of MCF-7 cells.