The collateral disease theory is a unique component of the theoretical system of traditional Chinese medicine (TCM), which is currently applied to all kinds of diseases related to the collaterals. With the in-depth study of collaterals theory by many practitioners, its advantages in differentiating and treating gynecological diseases are gradually embodied. Based on the theory of collaterals disease, we discussed the pathogenesis, syndrome differentiation and treatment of gynecological diseases, concluded that the deficient collaterals under nourishment and the stagnant and blocked uterine collateral are the important pathogenesis of gynecological illness. Then we pointed out that invigorating the spleen and tonifying the kidney, and unblocking collateral and dissipating stasis are important treatment methods. We discussed the application of collateral disease theory in Tianjin HA’s gynecology, and provided certain theoretical basis and clinical reference for the treatment of gynecologic diseases.