HCC cell‐secreted exosomal PSMA5 knockdown inhibited the exosome‐induced effect on macrophages, and attenuated the promotion induced by exosome‐treated macrophages on HCC cell migration/invasion and tumorigenesis along with in vivo M2 polarization and JAK2/STAT3 pathway activation. The gene discussed is PSMA5; the disease is hepatocellular carcinoma.