To provide a matrix arithmetic operation method and device for quickly operating a desired matrix arithmetic operation only by setting the resistance value of variable resistors constituting a matrix circuit in a simple constitution, and setting a voltage value to be applied to a line- or column- direction wiring.

This device is provided with plural variable resistors 110-125 having resistance corresponding to each coefficient of a matrix Aij of a multiplicand which are wired like a matrix, voltage controlling parts 12 for impressing a voltage corresponding to the coefficient of a matrix Xj of a multiplier to the column-direction wiring of the plural variable resistors, and current measuring equipment 13 for measuring a current value running through each line- direction wiring. The current value measured by the current measuring equipment 13 includes the multiplied result of the matrix Aij of the multiplicand by the matrix Xj of the multiplier.