A collapsible high chair is provided. The collapsible high chair comprises a front frame including a pair of middle front tubes and a substantially U-shaped lower front tube, the pair of middle front tubes and the lower front tube being detachably engaged with each other by fastening devices; and a rear frame including a substantially U-shaped upper rear tube and a substantially U-shaped lower rear tube, the upper rear tube and the lower rear tube being detachably engaged with each other by fastening devices. The front frame and the rear frame are pivotally connected to each other so that the front frame and the rear frame pivot and approach with respect to each other, thereby allowing the high chair to be in a collapsed state.