Disclosed is a random binary sequence-based sequence encryption method accompanied with random reconfiguration of a key. The method is mainly characterized in that (1) an existing random sequence is used to dynamically configure a seed random sequence at the beginning of each encryption operation, (2) the seed random sequence is used to pseudo-randomly configure a random key with a fixed-length or variable-length bit field, (3) the pseudo-random configuration of the random key accompanies an encryption process, (4) a transitive property of an exclusive-or operation is used to realize a variable-frequency nonlinear exclusive-or operation on a plaintext using the key, (5) adjustment of key configuration is realized by adjusting a characteristic vector, other operation vectors and a pseudo-random configuration function, such that adjustment of an encryption density can be realized without increasing time complexity, and (6) the characteristic vector are unable to be reversely inducted in polynomial time complexity.