The bolt connection is the main way of mechanical connections for aero-engine. The traditional torque method causes a large pre-tightening error, which reduces the connection quality to some extent. Therefore, the key connection structure of an engine low-pressure turbine disk and shaft is taken as subject, which is combined with the traditional torque method and the advanced angle method. For the first time, in the domestic engine assembly, the “torque control + angle monitoring” method is applied, and the intelligent tightening system is developed. Taking use of high precision of the pre-tightening force by angle method, when the torque is accurately applied, the rotation angle of nut is monitored to adjust to ensuring the precise control and the uniformity of the joint rigidity, and the structural connection quality of the engine is improved, which is going to provide technical means for subsequent process co-design of engine and solutions to engine assembly inconsistencies.