In order to solve the problem of error code in the field of phase unwrapping based on phase-shift technology combined with structured light binary code, a new complementary structured light binary code was presented. Two kinds of complementary encoding and decoding modes were designed by projecting one more Gray code image as well as taking advantage of the property of Gray code that the Hamming distance of the neighbor code is one. By using the new codes which mode error code happen at different positions, and combining with phase-shift technology make the problems of error code in the process of phase-unwrapping solved. The design and property of the complementary structured light binary code was discussed, and then the process of phase-unwrapping based on complementary structured light binary code was analyzed in detail. Computer simulation and three-dimensional experiments prove the complementary structured light binary code practicable and reliable.