Zeolite P was synthesized via in-situ hydrothermal method with metakaolin-based geopolymer (SiO₂/Al₂O₃=3.2) as a staring material. The major factors influencing the crystallization and morphology of Zeolite P were investigated in the aspects of hydrothermal temperature,concentration of sodium hydroxide solution and hydrothermal time.The results showed that zeolite P was successfully transformed from metakaolin-based geopolymer at 100℃ curing for 24 h in the sodium hydroxide solution of 2.0 mol/L.Being simple, environment-friendly and controllable,the in-situ hydrothermal method is expected to be used to synthesize other zeolites by changing the raw material compositions and reaction conditions.