To provide the electronic zoom device in which magnification processing in the vertical direction is conducted while reducing uneven resolution without increasing the circuit configuration.

A circuit of the device to apply magnification processing to an image signal in the vertical direction is made up of a multiplier 20 that multiplies an interpolation coefficient Ka with a signal by one line delayed by a line memory 10, a multiplier 21 that multiplies an interpolation coefficient Kb with a signal by one line delayed by a line memory 11, and a multiplier 22 that multiplies an interpolation coefficient Kc with a signal by one line delayed by the line memory 11, and the interpolation coefficients Ka, Kb, Kc given respecively to the multipliers 20, 21, 22 are calculated by an interpolation coefficient generating circuit 4. Each of the interpolation coefficients Ka, Kb, Kc is decided such that the interpolation processing using two image signals by one line among three image signals by one line or the interpolation processing using three image signals by one line is adaptively selected depending on a common difference (d) in response to the magnification and an interpolated position.