This invention relates to an overcurrent protection device, which comprises a housing having a first side mounted with first and second wire terminals and a second side installed with a button, an elastic element installed therein for abutting against the button, a memory alloy plate disposed therein and having a first end connected to the first wire terminal and a free end having a first contact, and an elastic metal sheet having two ends movably connected to the first and free ends respectively. When the button is pressed, an extended rod thereof can push the first contact and cause the memory alloy plate to be deformed for enabling the first contact to contact a second contact on the second wire terminal. When the button is released and shifted away from the first contact, a space will be provided for the first contact to return an original status prior to deformation.