The primary chemical element of cannabis, cannabidiol (CBD), has been proven to have antitumor properties. The current research examined the in vitro results of CBD on human gastric most cancers SGC-7901 cells. We discovered that CBD considerably inhibited the proliferation and colony formation of SGC-7901 cells. Additional investigation confirmed that CBD considerably upregulated ataxia telangiectasia-mutated gene (ATM) and p53 protein expression and downregulated p21 protein expression in SGC-7901 cells, which subsequently inhibited the degrees of CDK2 and cyclin E, thereby leading to cell cycle arrest on the G0-G1 part. As well as, CBD considerably elevated Bax expression ranges, decreased Bcl-2 expression ranges and mitochondrial membrane potential, after which upregulated the degrees of cleaved caspase-Three and cleaved caspase-9, thereby inducing apoptosis in SGC-7901 cells. Lastly, we discovered that intracellular reactive oxygen species (ROS) elevated after CBD therapy. These outcomes indicated that CBD might induce G0-G1 part cell cycle arrest and apoptosis by rising ROS manufacturing, resulting in the inhibition of SGC-7901 cell proliferation, thereby suggesting that CBD might have therapeutic results on gastric most cancers.