The invention discloses a direct current magnetic bias fault simulation structure for a transformer. The direct current magnetic bias fault simulation structure comprises a three-column type transformer core, a smooth and adjustable direct-current current source, a first direct current magnetic bias coil and a second direct current magnetic bias coil, wherein the first direct current magnetic bias coil is wound on a left lower iron yoke of the three-column type transformer core; the second direct current magnetic bias coil is wound on a right lower iron yoke of the three-column type transformer core; one end of the first direct current magnetic bias coil is connected in series with one end of the second direct current magnetic bias coil; the other end of the first direct current magnetic bias coil is connected with a first lead-out wire; the other end of the second direct current magnetic bias coil is connected with a second lead-out wire; the first lead-out wire and the second lead-out wire are connected to the smooth and adjustable direct-current current source; the winding direction of the first direct current magnetic bias coil on the left lower iron yoke is the same as the winding direction of the second direct current magnetic bias coil on the right lower iron yoke. According to the direct current magnetic bias fault simulation structure, direct current magnetic bias faults under multiple working conditions can be accurately simulated, and research and proving test of the direct current magnetic bias fault of the transformer are finished.