Based on the theory of collateral diseases，the characteristics of gynecological abdominal mass correspond to collateral diseases，and its essence belongs to collateral diseases.Qi stagnation of collaterals is the initial stage of its occurrence.Phlegm，cold and blood stasis in uterine collaterals are the common mechanism of diseases.Damage of collateral vessels is the reason for its development，and collaterals being void and defenceless is the root cause of its occurrence.During treatment，attention should be paid to both “dredge” and “benefits”.Through discussion，the paper hopes to further enrich the theoretical guidance and scientific connotation of collateral disease theory in the field of gynecological reproduction，and provide new ideas and methods for the diagnosis and treatment of clinical gynecological abdominal mass.