a nonvolatile semiconductor memory device comprising a storage element which is programmed with information by varying electrical properties irreversibly , a selection switch connected in series to the storage element , a protection element connected in parallel to the storage element to protect the storage element from irreversible variations of electrical properties when the storage element is unprogrammed , a first activation circuit which activates the selection switch , a second activation circuit which activates the protection element in complement with the first activation circuit in normal mode , and a test circuit which conducts a test on the storage element while the second activation circuit is activating the protection element together with the first activation circuit in test mode .