The high expression of METTL3 indicated a poor prognosis of HCC. A: Correlation analysis of METTL3 and tumor lymph node metastasis in patients (n=50); B: Correlation analysis of METTL3 expression and tumor size in patients (n=50); C: Correlation analysis of METTL3 expression and TNM stage of patients (n=50); D: By analyzing Kaplan-Meier Plotter database, patients with high METTL3 expression had a worse overall survival prognosis (n=364); E: By analyzing Kaplan-Meier Plotter database, patients with high METTL3 expression had a worse relapse free survival prognosis (m=316); F: By analyzing Kaplan-Meier Plotter database, patients with high METTL3 expression had a worse progression free survival prognosis (n=370); G: By analyzing Kaplan-Meier Plotter database, patients with high METTL3 expression had a worse disease-specific survival prognosis (n=362). Compared with <5 cm tumors, *P<0.05; compared with negative lymph node metastasis or I+II tumors, **P<0.01.