PURPOSE: To shorten the echo time and repeating time by performing data sampling in the whole period when the frequency encoding gradient magnetic field is applied including the rising and trailing period, and converting the data into the data when the gradient magnetic field is constant.

CONSTITUTION: Data sampling pulses of an A/D converter are generated in the whole period including the rising and trailing period of frequency encoding gradient magnetic field Gr pulses, and data sampling is performed in the whole period of the Gr pulses. The data obtained in the rising and trailing period when the gradient magnetic field intensity is less sufficient than at the normal time are converted into the data when the gradient magnetic field intensity is made constant, then data interpolation is performed.