本发明公开了一种近临界水介质中氨催化菲汀水解制备肌醇的方法。方法的步骤如下:1)在高压反应釜中加入去离子水和菲汀,去离子水与菲汀质量比为1∶1～6∶1,开搅拌,升温至100℃,打开排气阀2～5分钟,利用水蒸气带走釜内的氧气;2)用高压计量泵将25%氨水加入釜内,使反应液中氨浓度达到0.5～20g/L,继续升温至200～350℃水解10～120min;3)水解完成后,降温, The invention discloses a method for preparing inositol by catalyzing liptin hydrolysis in a near-critical aqueous medium. The steps of the method are as follows: 1) adding deionized water and statin in a high pressure reactor, deionized water and filtin weight ratio of 1: 1 ~ 6: 1, stirring, raising the temperature to 100 DEG C, opening the exhaust valve 2 ~ 5 minutes, the use of steam to take away the oxygen inside the autoclave; 2) with a high pressure metering pump 25% ammonia added to the kettle, the reaction liquid ammonia concentration 0.5 ~ 20g / L, continue to heat up to 200 ~ 350 ℃ hydrolysis 10 ~ 120min; 3) hydrolysis is completed, cooling,