The utility model discloses a warm school uniform with detachable inner bag, include: the outer cloth cover, the left and right sides of outer cloth cover are connected with the sleeve, the rear end middle of outer cloth cover is installed with a plurality of connecting buttons at equal intervals, the rear end top of outer cloth cover is installed with the positioning button, and the rear end right side of outer cloth cover is sewed with the pocket, the inner chamber of outer cloth cover is sewed with the inner cloth cover, the outer cloth cover and inner cloth cover bottom are connected with the zipper and are sewed, the front end top of outer cloth cover is installed with a plurality of positioning mechanisms, the outer cloth cover and inner cloth cover are provided with the heat preservation inner bag in, when the heat preservation inner bag is placed into the middle of outer cloth cover and inner cloth cover, the button cap and button insert block are positioned with the snap, and it is convenient to fix it, when needing to separate the heat preservation inner bag, only need to pull the pull block, drive T type board to move upwards, make the trapezoidal block on connecting plate and sliding block shrink, can separate it, improve the convenience of this device split.