Provided is a technique for improving spatial resolution contrast of an ultrasonic tomogram compared with a method based on a coherence between echo signals. The present invention provides an ultrasonic tomogram generation method including: an estimation step SA100 of estimating noise in echo signals of M channels output from an ultrasonic probe, which receives echoes of ultrasonic waves emitted from M (being a natural number of 2 or more) ultrasonic transducers and outputs an echo signal, and calculating a weight coefficient for emphasizing an echo from a reception focus according to a signal-to-noise ratio in the echo signals of the M channels; and a generation step SA110 of generating a beamformer representing an ultrasonic tomogram from the echo signals of the M channels, using the weight coefficient calculated in the estimation step SA100.