The invention relates to an anti-collision card swiping method and an anti-collision card swiping device for a distributed agricultural irrigation charge control system. On the basis of a CSMA/CA algorithm, a MacMinBE value is adjusted according to a node quantity of a card swiping machine tool in previous multiple times of communication and a weighted value of the number of previous multiple times of communication backoff, in view of influence of the quantity of card swiping machine tools and the number of information send times on the MacMinBE; when the quantity of card swiping machine tools is more than the weighted value of the quantity of the card swiping machine tools in the previous multiple times of communication, and NB is more than the weighted value of the previous multiple times of communication backoff, the MacMinBE is added with 1; when the quantity of the card swiping machine tools is less than the weighted value of the quantity of the card swiping machine tool nodes in the previous multiple times of communication, and the NB is less than the weighted value of the previous multiple times of communication backoff, 1 is subtracted from the MacMinBE. According to the method and the device provided by the invention, self-adapting adjustment of the MacMinBE is achieved, a communication success rate of the multiple card swiping machine tools simultaneously communicating with an agricultural irrigation charge control terminal is improved, normal use of a user is ensured, and user experience feeling is enhanced.