Objective To verify the feasibility and accuracy of the "lung surface intersegmental constant proportion landmarks", developed by our center, in identifying intersegmental planes during pulmonary segmentectomy. MethodsWe prospectively enrolled the patients who planned to receive thoracoscopic segmentectomy in West China Hospital of Sichuan University and The Third People's Hospital of Chengdu from September 2021 to October 2021. We took a relatively objective and feasible method, intravenous injection of indocyanine green, in identifying intersegmental planes as standard control. We intraoperatively judged the consistency between "lung surface intersegmental constant proportion landmarks" and intravenous injection of indocyanine green in identifying intersegmental planes. We discerned main landmarks of intersegmental plane by the constant proportion segment module, which was built based on the "lung surface intersegmental constant proportion landmarks", as well as distinguished the planes with discrepant fluorescence by peripheral intravenous indocyanine green injection. When the distance between the landmarks determined by the "ung surface intersegmental constant proportion landmarks" and the segmental boundaries displayed by indocyanine green fluorescence staining was ≤1 cm, the landmarks were judged to be consistent with the planes with discrepant fluorescence. As long as one of the landmarks was judged to be consistent, the method was considered to be feasible and accurate. Results A total of 21 patients who underwent thoracoscopic segmentectomy were enrolled, with 5 male and 16 female patients. The median age was 55 years, ranging from 34 to 76 years. A total of 11 patients received left-side surgery, while 10 patients received right-side surgery. In the operations of 21 pulmonary segmentectomies, at least one intersegmental landmark determined by the "lung surface intersegmental constant proportion landmarks" was consistent with the intersegmental plane determined by indocyanine green fluorescence staining in each patient. ConclusionThe intersegmental landmarks determined by the "lung surface intersegmental constant proportion landmarks" are consistent with that determined by indocyanine green fluorescence staining. The method of "lung surface intersegmental constant proportion landmarks" is feasible and accurate in identifying intersegmental planes during pulmonary segmentectomy.