The invention relates to a method for preparing a solar module, comprising the steps of: brushing a soldering flux on a PCB (Printed Circuit Board) and brushing solder paste on each corresponding bonding pad on a PCB fixing board; placing a plurality of whole solar wafers corresponding to a plurality of areas on the PCB board to corresponding welding positions of the PCB fixing board, wherein scratches are arranged among all areas of the whole solar wafers in advance; welding the solar wafers onto the PCB board; and pressurizing the scratches among all areas of the whole solar wafers to ensure that the whole solar wafers are split into a mutually independent group. The method provided by the invention has the beneficial effects that: a method of first welding and then separating a big solar wafer is adopted so that the work efficiency can be increased by several times, the occupied area is decreased and the product is tidy and attractive in appearance; and the space between welding spots is widened a lot by utilizing an insulation layer so that the short circuit between a positive electrode and a negative electrode during welding is completely avoided, the back repair rate is greatly decreased, the finished product rate is increased and the production cost is reduced.