The invention relates to a machining method for soldering micro-strip boards by using printing solder paste. The machining method comprises the following operation steps: (1) the micro-strip boards and substrates are cleaned; (2) four or more cleaned substrates are respectively placed in positioning grooves of positioning baseplates; (3) net plates are placed on the four or more substrates; and mesh units uniformly distributed on the net plates are respectively corresponding to the four or more substrates; (4) the net plates are uniformly coated with the printing solder paste; and (5) the net plates are taken down; the corresponding micro-strip boards are placed on the uniformly deposited solder paste; and each micro-strip board is corresponding to one substrate to form a welding module. The conventional steps of pressing block fixation, welding, pressing block disassembly, cleaning and detection are performed; reflow soldering is adopted; and the reflow soldering is performed by four temperature phases. The machining method saves such complex operation flows as solid-state soldering lug shearing, size control, oxide layer removal, screw hole protection, solder resisting adhesive tape protection and flux coating, reduces the machining cost, and is high in product soldering rate and suitable for batch production.