The invention relates to a rotary shaft torque force testing and detection device. A front supporting plate and a rear supporting plate are mounted at front and rear positions of one end of a bottom plate respectively; the front supporting plate is sequentially provided with a driving gear and a front mounting seat through a bearing; a rear mounting seat is fixed on the rear supporting plate; a test piece is arranged between the front mounting seat and the rear supporting seat through a fixed bolt; a cover body is mounted at the top between the front supporting plate and the rear supporting plate; a positioning shaft is arranged on a side face of the driving gear; the front end of a chain is connected onto a positioning shaft and is engaged and connected with a driving gear; a base is arranged at an end part of the bottom plate; the tail end of a cylinder body is mounted on the base; a pull ring is connected with the cylinder body through a retractable rod; the rear end of a pulling force sensor is connected onto the pull ring through a connecting rod; the front end of the pulling force sensor is connected with the tail end of the chain. According to the technical scheme, the rotary shaft torque force testing and detection device with the advantages of reasonable structure, convenience in operation, low labor intensity, high detection efficiency and accurate detection result can be provided.