The invention discloses an instrument capable of implementing automatic detection and sorting of bearing inside diameter. A double-path symmetrical structure is adopted, an inlet sorting mechanism is fixed on one side of a conveyor belt, the side of the conveyor belt is provided with a feeding cylinder and a feeding rod, the other side of the conveyor belt is provided with a station, the station is provided with a station clamping plate and a push plate which are fixed on a station clamping cylinder, the station clamping cylinder is fixed on a station push cylinder, one side of the station is provided with an inside diameter detection mechanism, the station is provided with two gaps which are communicated with a reject outlet and a repair outlet respectively, a reject zone baffle plate and a repair zone baffle plate are arranged on the two gaps respectively, an outlet sorting hopper is fixed at one end of the station, an outlet sorting block is arranged below the outlet sorting hopper, the outlet sorting block is fixed on an outlet sorting cylinder, two sides of the outlet sorting block are provided with an outlet push cylinder and a small groove respectively, and two sides of the small groove are provided with a discharge plate and a discharge frame respectively. The instrument can ensure the reliability of detection on the premise that the detection efficiency of the bearing inside diameter is not reduced, and realizes automation of feeding, detection and sorting.