An anti-fuse circuit includes: a rupture unit including an anti-fuse programmed in response to an input rupture signal during a program mode, and configured to generate an output rupture signal corresponding to a state of the anti-fuse to output the generated output rupture signal to a transmission node, a voltage clamp unit configured to generate a clamp voltage proportional to an external voltage level to generate the clamp voltage having a constant voltage level when the external voltage level rises to a predetermined level or more, and a fuse signal generation unit configured to reset the transmission node to the clamp voltage at the initial stage of the program mode to generate a fuse signal in response to the voltage level of the transmission node during an output mode.