A semiconductor memory apparatus using tunnel magnetic resistance elements comprises a plurality of cell arrays. When data is read from a cell in one of the cell array, a word line connected to the cell is connected to a voltage source, a bit line connected to the cell is connected to an input of a sense amplifier, word lines in the cell array concerned except for the word line connected to the cell and bit lines in the cell array concerned except for the bit line connected to the cell are isolated. A subtracter subtracts an offset current which is generated in another cell array from a current flowing from the bit line connected the cell. An integrator integrates the result of the subtraction. A comparator, a read current value register, and a reference value register performs self-reference reading method on the result of the integration.