PURPOSE: To relieve the defective memory cell of another block with the redundant memory cell of a special certain block by controlling the output of a block selecting signal generating circuit with a selecting signal to the redundant memory cell of the prescribed block.

CONSTITUTION: The output of a block selecting signal generating circuit 20 is controlled by passing a redundant memory cell selecting signal of a decoder 19 for redundancy through an AND gate 21, an OR gate 22 and an inverter 23. When the selecting signal 18 is in a selecting condition 'H', a left block selecting signal 24 is forcibly caused to be non-selection and a right block selecting signal 25 goes to the selecting condition. At such a time, a redundant memory cell 17 is selected. When the selecting signal 18 is the 'L' of non- selection, the output of the block selecting signal generating circuit 20 is given to a decoder 12 as it is and the right or left block is selected. Thus, the redundant memory cell of a certain block is used also as the redundant memory cell for the other block and the defective memory cell of the other block can be also relieved.