A bearing unit of a turbocharger may be disposed on an inner side of a space in a center housing and carry axial load of a rotary shaft connecting a turbine wheel, a compressor wheel, and an electric motor. The bearing unit may include a bearing body fastened to a side of the center housing and has a through-hole substantially at a center of the bearing body, and a coupling disposed in the through-hole and on the rotary shaft, having a stepped portion in which the bearing body is inserted, and forming an oil chamber with the bearing body.