An ultrasound diagnostic apparatus includes: an ultrasound probe that performs ultrasound transmission/reception in Doppler mode and ultrasound transmission/reception in other mode than Doppler mode and a Doppler processing unit that performs quadrature detection on an echo signal generated from the ultrasound transmission/reception for Doppler mode and then generates a Doppler spectrum signal. The Doppler processing unit includes a signal estimation unit that performs an extrapolation process to estimate missing part of the Doppler spectrum signal resulting from the ultrasound transmission/reception for other mode.
