The utility model provides a voltage transformer auxiliary device for testing, include: the insulation board, first terminal A, second terminal N, third terminal 1a, fourth terminal 1n, the 5th terminal 2a, the 6th terminal 2n, the 7th terminal da, the 8th terminal dn, the 9th terminal X, first single -phase air switch, the single -phase air switch of second, the single -phase air switch of third, the single -phase air switch of fourth, a connecting wire, the 2nd connecting wire, the 3rd connecting wire, fourth connecting wire, the 5th connecting wire, the 6th connecting wire, the 7th connecting wire, the 8th connecting wire, the accuracy of tentation data has been guaranteed. Because voltage transformer auxiliary device for testing adopts the direct crimping of connecting wire and voltage transformer secondary winding, has made things convenient for the inspection, has got rid of the influence of bad connection to obtain comparatively accurate tentation data.