The present invention relates to an infusion device comprising a clamp having a through hole that is configured to allow an infusion tube to pass through therethrough, and further having a baffle wall; a block having a mounting hole and an opening; a pressure member pivoted to the block and configured to press towards the baffle wall and close the infusion tube, wherein a position of the opening corresponds to the pressure member; and a handle pivoted to the block and having a protrusion that is configured to pass through the opening and push up against the pressure member so as to make the pressure member away from the baffle wall when the handle rotates towards the block around an axis, so that the infusion tube is no longer closed by pressing of the pressure member.