The anti-cancer effects and the tumor-targeting of rhVEGF121KDR/rGEL fusion toxin in human tumor xenografts models were investigated for the development of more effective and safer anticancer drugs.Human carcinoma xenografts models of hepatoma SMMC-7721 cells, esophageal carcinoma KYSE-150 cells, gastric carcinoma SGC-7901 cells and colon carcinoma HT-29 cells were established, tumor volume was measured every 2-3 days after administration, tumor growth curve was drawn, and the relative tumor growth rate was calculatedThe localization of fusion toxin in tumor tissues was examined by immunohistochem.The volume of human carcinoma xenografts of SMMC-7721, KYSE-150, SGC-7901 and HT-29 was resp. (89.33 ± 56.36) mm3, (142.47 ± 58.67) mm3, (73.80 ± 31.05) mm3 and (79.64 ± 34.46) mm3 in the treated group, and (328.19 ± 200.27) mm3, (474.05 ± 167.42) mm3, (172.34 ± 41.78) mm3 and (480.26 ± 348.34) mm3 in the untreated group.The relative tumor volume (RTV) of the four human carcinoma xenografts in the treated group was resp. 5.31 ± 2.13, 5.72 ± 2.45, 3.59 ± 1.55 and 5.82 ± 1.92, and in untreated group, the RTV was resp. 17.10 ± 6.00, 23.71 ± 10.36, 11.65 ± 4.14 and 23.24 ± 5.74.The relative growth rate was resp. 31.05%, 24.12%, 25.04% and 30.82%.Both tumor volume and RTV of human carcinoma xenografts treated with the fusion toxin demonstrated significant reduction compared with untreated controls (all P < 0.01).In conclusion, the rhVEGF121KDR/rGEL could significantly inhibit tumor growth in at least four xenograft models, and was a promising candidate drug for the targeted therapy of cancer.