To solve such a problem that in a rewritable non-volatile semiconductor memory, it is hard to judge whether intended voltage is applied or not in various disturbance evaluations and tests, also a test time for evaluation and test of a block erasure function is increased as increment of the number of erasure blocks and rewriting stress for a memory cell at a test is increased.

This storage is provided with a memory cell 2 for monitoring, of which the control gate 3 is made common with a memory cell array 1 and in which a source and a drain can be controlled independently and electrical write-in and erasure can be performed, and at the time of evaluation and test, it is confirmed that intended voltage is surely applied by a function of simultaneous selection of plural word lines, a function of simultaneous selection of plural bit lines, and a function of simultaneous selection of source lines.