According to the characteristics of the ambiguous Doppler velocity in the velocity-azimuth profile, a technique of tangential remove for ambiguous velocities is proposed in the paper. The process of removing the ambiguous velocities contains four major steps: Dividing the velocity-azimuth profile into zero segment (data gap), unambiguous segment, and ambiguous segment by removing the isolated points on the profile. Using the unambiguous segment with opposite signs at two ends as reference to determine the ambiguous segments and using the continuity of velocity distribution to remove the ambiguous velocity segments on the profile. Using the simulated harmonic curve of profile as reference to determine and remove the ambiguous points on the profile. Using one of the ambiguous velocity removed profile in a distance range as reference to remove ambiguous velocity according to the radial continuity of velocity distribution. The ration of the amplititude of simulated harmonic curve of profile to the average of the absolute value of Doppler velocity is used to check whether the ambiguous velocities are removed on a velocity-azimuth profile.