A non-volatile semiconductor storage device includes: one or more memory cells including anti-fuse elements capable of writing data by breaking down a gate insulation film of a MOS transistor with a high voltage; a sense node having its one end connected to each of the anti-fuse elements; a sense amplifier comparing the potential of the sense node with the reference potential and amplifying the difference therebetween, the sense amplifier being activated according to a sense-amplifier activation signal; an initialization circuit initializing the potential of the sense node according to an initialization signal; a control circuit outputting the initialization signal at a predetermined timing after input of an external signal input from the outside and outputting a first activation signal to activate the sense amplifier at a predetermined timing after input of the external signal; and a switching circuit outputting the first activation signal as the sense-amplifier activation signal when a normal data read operation is performed, and outputting an inverted version of the external signal as the sense-amplifier activation signal when a test execution is instructed for the one or more memory cells before the gate insulation film is broken down.