The aim of this study is to investigate the cell reparative effects of Mormordical Charantia Linn. boiling water extract (MCE) on the HIT-T15 Hamster Pancreatic β-cells. Furthermore, the superoxide dismutase (SOD) activity of MCE was determined. 0.02% MCE (w/v) achieved the highest cell proliferation rate of 45.6% (p<0.01) on alloxan damaged HIT-T15 cells while 0.2% MCE increased the proliferation of the normal cells by 35.4% (p<0.05). The high molecular weight fraction of MCE (MHMF, MW>3 kDa) showed the stronger effects in repairing alloxan damaged cells (cell proliferation rate=32.1%, p<0.05) than that of the low molecular weight fraction (MLMF, MW≤3 kDa), while the latter showed the higher activity on increasing insulin secretion of normal or damaged cells. 2%MCE and MLMF showed the highest SOD activities, 19.74 NU/mL and 19.84 NU/mL, but they failed to improve the proliferation rate of alloxan damaged cells. These results indicated MCE has significant repairing effects on HIT-T15 cells against superoxide anion radicals, which did not correlate to MCE's SOD activity. It was hypothesized that the different fractions of MCE may make different contributions to MCE's cell repairing activity and its ability of stimulating insulin secretion.