The invention provides an efficient special tool for overall welding of a framework. A machining platform is included, and on the two sides of the top of the machining platform, semi-shaft positioningsupports, front positioning supports, auxiliary positioning supports and supporting lug positioning supports are symmetrically arranged in sequence from one end to the other end; the inner sides of the two front positioning supports are each provided with a front lower joint supporting block; the inner sides of the two auxiliary positioning supports are each provided with an auxiliary supportinglower joint supporting block; the portions, on the inner sides of the front lower joint supporting blocks, of the machining platform are each provided with a supporting disk positioning support; and the portions, on the inner sides of the two supporting lug positioning supports, of the machining platform are each provided with a supporting disk positioning support. During welding, the efficient special tool for overall welding of the framework avoids the out-of-tolerance phenomenon occurring on the size of the machined framework, a positioning point for overall welding of the framework can bedetermined more accurately, and the machining precision is guaranteed; and a sufficient actual operation space is reserved for the efficient special tool for overall welding of the framework accordingto the technological process, a technician can perform operation more easily, the welding period is shortened, and the work efficiency is improved.