The present invention discloses a ZUC sequential cryptographic algorithm mask protection method for Boolean masks as round numbers, which comprises the steps of (1) selecting a to-be-masked round number, initializing first N rounds, and respectively adopting m0, 1=m1, m0,2=,2 exclusive OR, as an input; (2) converting the exclusive-or operation into the Add operation through a transition function h(x, y); (3) converting the Add operation into the exclusive-or operation through a transition function g(x, y); (4) shifting and respectively conducting the linear L1 operation and the linear L2 operation; (5) conducting the operation on left and right S boxes to obtain a new SL' and a new SR'; (6) conducting the output operation W for f function. According to the technical scheme of the invention, the mask value of each node is different from those of other nodes by means of the above mask protection method. Meanwhile, the output mask value of an S box during each round is also different from those of other boxes. Therefore, the first-order analysis on the Hamming weight and the Hamming distance is disabled. In addition, no leakage point is available for the second-order analysis on the Hamming weight and the Hamming distance.