Objective: To investigate the effects of VEGF-C antisense RNA on the in vivo growth of colorectal carcinoma LoVo cells. Methods: Twenty nude mice were equally randomized into experimental group and control group. Mice in experimental group were inoculated with anti-sense VEGF-C transfected LoVo cells, and those in control group were inoculated with empty plasmid transfected LoVo cells. The growth of the tumor xenografts in mice was observed. Finally, mice were sacrificed at 21 d after inoculation, and the microlymphatic density (MLD) and microvessel density (MVD) in tumor xenograft tissues were measured through immunohistochemical staining. Results: There was no difference in tumor formation rates between the two groups (both were 100%). The volumes of the implanted tumor in experimental group and control group were (382.0±152.8) mm3 and (454.2±148.7) mm3 at 14 d post-inoculation, and were (745.0±250.9) mm3 and (1 574.4±506.2) mm3 at 21 d post-inoculation respectively, and the differences between them had statistical significance (both P<0.05). Both MLD and MVD in the tumor tissues from experimental group were significantly lower than those from control group [(11.75±2.22)/0.72 mm2 vs. (28.50±2.65)/0.72mm2, (47.75±2.99)/0.72 mm2 vs. (53.73±3.50)/0.72 mm2] (both P<0.05). Conclusion: The growth of colorectal carcinoma LoVo cell xenografts in nude mice can be suppressed by VEGF-C antisense RNA transfection and that may also inhibit the lymphangiogenesis and angiogenesis in tumor xenografts.