In this study, we showed that the Csnk1a1 inhibitor D4476 obviously inhibited GBM cells, regardless of TP53 mutation status (TP53 mutant types, U251, LN229, T98G, LN18 cells and TP53 wild‐type, U87 and A172 cells). D4476, an inhibitor of the intracranial GBM model, prolonged mouse survival. The gene discussed is CSNK1A1; the disease is glioblastoma.