The invention relates to a low-interaction-overhead counter synchronization method. The method comprises the steps of splitting a time counter value of a sending end; sending a low part of a counter value of the sending end; extracting the low part of the counter value of the sending end by a receiving end; splitting a time counter value of the receiving end; and through comparison of the low parts of the counter values of the sending end and the receiving end, carrying out restoration at the receiving end, thereby obtaining the time counter value of the sending end, and realizing the synchronization of counters of the communication sending end and receiving end. The method is applicable to a communication system with limited channel resources; in a data communication encryption application, according to the method, cipher information of the two communication parties is synchronized with low interaction overhead; and accurate encryption and decryption behaviors of the sending end and the receiving end are realized.