The invention relates to a weighing method for an electronic belt scale capable of self-check, more than two weighing carrier rollers (3) form into a weighing device of the electronic belt scale, each weighing carrier roller is supported by more than two weighing sensors (5), each weighting sensor is respectively connected with a PLC (7) through an individual signal transmission line (8), the PLC can directly acquire an output weighing signal of each weighing sensor to monitor and diagnose each weighing carrier roller and weighing sensor on real-time in the weighing process. During a normal weighing, the method measures according to a multiple carrier roller mode. The PLC monitors, recognizes, diagnoses, groups and compares the weight signals after A/D transition on real-time, and calculates the material weight after integral arithmetic with speed signals of a motor or the belt. During thediagnosis, the weighing device treat according to more than two single carrier roller manners, and each weighing carrier roller is measuring cup for each other. The invention has strong ability of disturbance resistance, and can find out failures such as poor measuring accuracy, damaged weighing sensor, etc., the performance is stable and reliable, the failure point can be quickly checked out so as to be maintained conveniently, the maintenance capacity and component replacement quantity are in a small quantity.