The invention discloses an energy-saving shield segment assembling and positioning electro-hydraulic control system adopting a load-sensitive technology. The system comprises a motor, a variable pump, a two-position three-way proportional reversing valve, a variable cylinder, an overflow valve, a pressure reducing valve, a pressure compensating valve, a one-way valve, a multi-way valve, a balancing valve, a hydraulic lock, a hydraulic motor, a hydraulic cylinder, a moment rotation speed sensor, a displacement sensor and a pressure sensor. The multi-way valve with the pressure compensating valve in a segment assembling system is used for controlling the rotation speed of the hydraulic motor for driving the segment assembling machine to rotate and the moving speed of each hydraulic cylinder. The pressure sensor is used for detecting the pressure of a main oil passage of the system and the working pressure of each executer in real time; and a computer control unit is used for determining a variable pump control signal according to a system pressure signal, so that the displacement of the variable pump is changed with the load change so as to achieve load sensitive control. According to the invention, energy waste caused by continuous oil supply at the highest working pressure of the traditional system is avoided, the throttling loss and overflow loss are greatly reduced, and an obvious energy saving effect is obtained.