The invention belongs to the technical field of plant identification, and particularly relates to a sex identification method of diecious plants. The sex identification method of the diecious plants comprises thefollowing steps: (1) detecting leaf samples of plants with known sexes to obtain electrochemical fingerprint standard spectrograms corresponding to the leaf samples of plants with different sexes; (2) detecting the leaves of plants with sex to be identified to obtain a detection result; and (3) comparing the detection result with an electrochemical fingerprint standard spectrogram to obtain the sex of the plant with the sex to be identified. According to the sex identification method of the dioecious plants, the dioecious plants are judged according to difference of the spectrums due to electrochemical behavior differences caused by different components in dioecious leaves of the same plant; and the identification method disclosed by the invention is simple, convenient and feasible, the cost is low, identification can be carried out at any time in any places, the accuracy is high, and the sex of the diecious plants can be identified rapidly.