In this study, the biological effects and molecular mechanism of recombinant RA538 and antisense c-myc adenovirus on human gastric, esophageal, 2BS and high-expression bcl-2 gene cancer cell lines were studied in vitro and in vivo. The results were as follows: Ad-RA538 and Ad-ASc-myc could strongly inhibit cell growth and induce apoptosis of SGC7901 cells in vitro and in vivo, and could down-regulate expression of c-myc, bcl-2 and cyclinD1 gene, up-regulate expression of bax gene. Ad-RA538 or Ad-AS c-myc could not inhibit cell growth and induce apoptosis changes of EC109, EC8712, 2BS and high-expression bcl-2 gene cancer cell lines, and could not down-regulate expression of c-myc and bcl-2 gene. The results indicated that: Ad-RA538 or Ad-AS c-myc can inhibit growth and induce apoptosis of gastric cancer cell in vitro and in vivo. They relate to c-myc, bcl-2, cyclinD1 and bax gene closely and play a key role on biologic effects in gastric cancer cells. Ad-RA538 and Ad-AS c-myc could not produce relevant changes on esophageal cancer, 2BS and high-expression bcl-2 gene cell lines.