Abstract： Objective To discuss whether the low molecular weight heparin (LMWH) can affect HLEC cell proliferation induced by the supematant of PANC-1. Methods To evaluate the anti-lymphangiogenic effect of LMWH on human lymphatic endothelial cell (HLEC) proliferation by an in vitro assay. Results The supematant of pancreatic cancer cell (PANC-1) could stimulate HLEC cell proliferation. There was significant deviation in HLEC proliferation between conventional culture (MTT: OD = 0.26 ± 0.02) and cultured with the supernatant of PANC-1 (MTT: OD =0.41 ±0.04). LOw concentration LMWH did not affect the proliferation of PANC-1 and HLEC cells, but suppressed HLEC cell proliferation induced by the supematant of PANC-1. Conclusion This study showes that PANC-1 supernatant plays an important role in promoting HLEC cell proliferation. Low concentra-tion LMWH is effective in inhibiting HLEC cell proliferation induced by the supematant of PANC-1.