A handle height adjusting mechanism of a stroller includes: a frame tube having a plurality of locating holes that are arranged at intervals in the axial direction, a handle tube disposed movably on the top end of the frame tube, a clamping member, a lock releasing member, an actuating member and a resilient member, wherein, the clamping member is positioned in the handle tube, the lock releasing member is movably connected with the inner of the handle tube and is interlinked with the clamping member, the actuating member is movably positioned on the handle tube and is joint with the lock releasing member, the resilient member is used for the restoration of the lock releasing member, the clamping member is capable of passing through a through hole of the handle tube, is clamped with a locating hole at a position of a selected height corresponding the through hole, and is capable of moving relative to the handle tube through the actuating member to drive the lock releasing member to move and to release the clamping of the clamping member and the locating hole through interlocking, thereby, the operations are simple and labor-saving, and the height of the handle tube can be adjusted by users themselves according to their requirements through remote controls.