The invention discloses a near-bit measurement while drilling (MWD) system and method. The method comprises the following steps: an alternating magnetic field is generated by assembling a strong-magnetic connector between a screw motor and a drilling bit; three components, namely a geomagnetic field, a gravity field and the alternating magnetic field, are measured by an MWD measurer which is arranged in a non-magnetic drill collar; the well deviation and azimuth of the position of the MWD measurer are calculated according to the three components, namely the geomagnetic field, the gravity field and the alternating magnetic field; the relative position between the MWD measurer and the strong-magnetic connector is calculated according to the alternating magnetic field; and the well deviation and azimuth of the position of the strong-magnetic connector are calculated according to the well deviation and azimuth of the position of the MWD measurer and the relative position between the MWD measurer and the strong-magnetic connector. The distance between the strong-magnetic connector and the drill bit is small, and the distance between the conventional strong-magnetic connector and the drill bit is less than 1m, so the well deviation and azimuth of the strong-magnetic connector can be treated as the well deviation and azimuth of the drill bit. Therefore, compared with the prior art, the technical scheme of the invention can be used for accurately measuring the well deviation and azimuth of the drill bit.