The invention discloses a non-tumor-causing MDCK cell line for amplifying influenza virus and a screening method thereof. The cell line is MDCK‑2B2, and the preservation number is CCTCC C201323. The present invention provides a non-tumorigenic cell line MDCK-2B2 and its subclone cell line, which grow into adherent cells and / or have epithelial-like morphology and / or can support the replication of various viruses, and can amplify Higher titer virus; In addition, the present invention has found a method for screening non-tumorigenic cell lines, which can assist the judgment of tumorigenicity through the growth rate of cells and the morphological changes of cells, that is, relatively slow-growing single-pore cells, which The tumorigenicity will be significantly reduced, and the appearance of giant cells will significantly increase the tumorigenicity. When screening non-tumorigenic cell lines on a large scale, such auxiliary judgment methods can shorten time and save costs.