Objective : The CRISPR / dCas9-SAM system was used to explore genes related to the proliferation of gastric cancer cells AGS，and their role in the occurrence and development of gastric cancer was analyzed． Methods : sgRNA was designed for genes with differential expression between gastric cancer and normal gastric tissue， and a lentiviral library was obtained after packaging was constructed．The AGS cells at different time points after the library was infected with AGS cells were used as the screening pressure，and the AGS cells at three time points on days 0，7 and 14 were collected．High-throughput sequencing analyzed sgRNA enrichment in AGS cells at dif- ferent time points after infection to obtain differential genes related to AGS cell proliferation. Results : Bioinformat- ics showed that compared with the 0 d group，42 and 45 negative screening differential genes and 59 and 40 posi- tive screening differential genes were obtained in the 7 d group and 14 d group，respectively．Among them，the 7 d group and the 14 d group had 11 genes in the negative screening and the positive screening． Conclusion In this study，11 genes inhibiting the proliferation of AGS cells were screened，of which 5 were protein-coding genes and 6 were long non-coding RNA ( lncRNA ) genes． 11 candidate genes that promoted AGS cell proliferation were screened，of which 3 were protein-coding genes and 8 were lncRNA genes．It laid a foundation for further function- al verification and comprehensive analysis of the occurrence and development process of gastric cancer.