The invention discloses a method for replenishing bags, which belongs to the technical field of packaging, and is characterized in that it comprises the following steps: a. First, detect multiple rows of material bags; b. If the material sequence is all empty, jump out and do nothing; c. In the first cycle, set the material sequence to be full and the feed slots of the waiting stations of the multi-column bag replenishing machine are all empty, and carry out the feeding action; d. In the next cycle, if there is a shortage of material in the bag replenishing slot , carry out replenishment action; if the replenishment bag trough is full, jump out without action; if the number of strip bags in the replenishment trough is greater than the number of empty bags in the replenishment trough, the replenishment action is still performed, several cycles Finally, if the number of strip bags in the feed tank to be replenished is less than the number of empty bags in the bag feed tank, the replenishment action is performed. The invention can ensure that in the next cycle, if there is no material bag in a bag replenishing trough, the bags in the trough to be replenished can always be replenished in time, and the whole bag replenishing process is smoother, thereby effectively improving the bag replenishment rate. efficiency.