Objective To construct the eukaryotic expressing plasmid of tumor necrosis factor-related apoptosis-inducing ligand(TRAIL),and study its inhibitory effect on hepatic tumor which implanted subcutaneously in nude BALB/c mice.Methods Total RNA of U937 cell was extracted, and its extracellular domain (114-281aa) was amplified by RT-PCR, then signal peptide was ligated. The recombinant secreting plasmid for TRAIL was constructed successfully which was confirmed by enzyme cleavage identification and sequencing identification. Liver cancer cell (strain No.7402) was implanted subcutaneously in 32 nude BALB/c mice. These mice were randomly divided into two groups: study group and control group. The mice in study group received muscular injection of plasmids for transfection, and the mice in control group received the injection of normal saline at the same time. The size of implanted tumors were measured continuously till the day of sacrificing, tumor cell apoptosis effect was examined by TUNEL method. Results In study group,tumor volume was smaller than that in control group and the blue-purple apoptosis cells were observed under microscope. Conclusion TRAIL plasmid can induce apoptosis of liver cancer cell and can inhibit the growth of liver tumor.