To provide a steering device enabling reduction of gear rattle noise of a rack shaft and a pinion shaft and a method of manufacturing the steering device.

A steering device includes a four-point contact ball bearing 50. The four-point contact ball bearing 50 includes an outer ring 51 attached to a housing 30, an inner ring 52 press-fitted to a pinion shaft 13 and rolling elements 53 disposed between the outer ring 51 and the inner ring 52, and supports the pinion shaft 13 rotatably relative to the housing 30. In the pinion shaft 13 and the four-point contact ball bearing 50, an inner ring deformation margin that is a value obtained by subtracting a radial clearance before press-fitting, which is a radial clearance of the four-point contact ball bearing 50 before it is press-fitted to the pinion shaft 13, from press-fitting interference, which is a difference between a pinion outer diameter before press-fitting that is an outer diameter of the pinion shaft 13 before the inner ring 52 is press-fitted to it and an inner ring inner diameter before press-fitting that is an inner diameter of the inner ring 52 before it is press-fitted to the pinion shaft 13, is included in a range of 8 μm or more and 22 μm or less.