A shift register unit includes: a pull-up node control unit; a pull-down control node control unit connected with a first level output terminal, and configured to control an electrical potential at a pull-down control node to be a second level when an electrical potential at a pull-up node is a first level, and to control a pull-down control node to be connected with a first level output terminal when the electrical potential at the pull-up node is a third level; a pull-down node control unit; a gate driving signal output unit; and a carry signal output unit configured to control a carry signal output terminal to output a carry signal under the control of the pull-up node and the pull-down node. The carry signal output terminal provides an input signal to a shift register unit in an adjacent next stage.