PURPOSE: To obtain large capacity associative storage device, high speed and low cost, by using low cost large capacity storage elements and introducing the method of series processing for bits.

CONSTITUTION: To a continuous readout data storage device 10, 8×64 sets of data in 16-bit are stored and they have different bit patterns but the data of bit patterns similar with each other are collected in the same block. A coding circuit 22 inputs an output from a parallel output terminal of an input shift register 20, the bit pattern determines a block address, which is inputted to a block address part of a block address register 21 and an output address register 26. When the operation of the initial value setting is finished, the highest order bit in the 16-bit is shifted out from the input shift register 20 and inputted in parallel with each comparison circuit 23.