Our study identified XPO5 as a potential substrate for B55β‐containing PP2A and further clarified that B55β‐containing PP2A can inhibit HCC progression by promoting XPO5‐dependent maturation of several tumor‐suppressive miRNAs, providing another potential mechanism to interpret the anti‐tumor role of PP2A. The gene discussed is XPO5; the disease is hepatocellular carcinoma.