To provide a coreless motor having a resin mold body having an accurate groove for generating a high dynamic pressure.

The coreless motor 1 comprises a motor housing 11, a rotary shaft 5 that is inserted into and is arranged at the center, a resin mold body 10 where a bearing section for rotatably supporting the rotary shaft 5 in the motor housing 11 and a cylindrical housing section that is fitted and arranged on the axial line of the rotary shaft 5 are integrated, a magnet 6 that is fitted and fixed to the outer periphery of the bearing housing, a cylindrical coil 7 for accommodating the magnet 6 within the diameter while being separated by a magnetic gap, a coil holder 8 for holding the coil 7 on the axial line of the rotary shaft 5, and a rectification mechanism 9 connected to the coil 7. In the coreless motor 1, the resin mold body 10 has an oil well that is formed on the inner periphery surface of the bearing housing, and a groove for generating dynamic pressures that is formed within a range whose depth is equal to or more than 0.1 μm and equal to or less than 5 μm.