Disclosed is a downhole electromagnetic flow transducer, which comprises a field core, a exciting coil, a short three-leg magnetic pole, a long three-leg magnetic pole, six electrodes, a coating and an insulated casing, wherein, the field core is a clava, exciting coil winds around the field core, the short three-leg magnetic pole and the long three-leg magnetic pole are drawn respectively from one of the two ends of the field core to the other end, various pole legs of the short three-leg magnetic pole and the long three-leg magnetic pole are inserted into the middle part of the corresponding gaps among the counterpart pole legs ,and forms a cage-like body enclosed by such six pole legs, the coating and the insulated casing are pipe-like bodies with six electrode holes arranged by an uniform distance around the walls in the middle of the coating and the insulated casing, the insulated casing are cased outside of the coating with their electrode holes corresponding mutually, the six electrodes are fixed on the electrode holes of the insulated casing without contacting with the walls of the electrode holes, the coating is cased on the cage-like body enclosed by the short three-leg magnetic pole and the long three-leg magnetic pole with the electrode holes distributed corresponding to the gaps of the magnetic poles of the cage-like body. The transducer has such advantages of high accuracy in flow measurement and high sensitivity.