ABSTRACT Objective To construct DynNom dynamic scoring model for breast cancer lymph node metastasis based on conventional ultrasound and ultrasonic shear wave elastic imaging parameters. Methods A total of 155 patients with breast cancer admitted to the hospital from July 2021 to December 2023 were selected as the study objects. Routine ultrasound and ultrasonic shear wave elastography were performed on all patients with breast cancer, and the patients were divided into a lymph node metastasis group and a group without lymph node metastasis according to their lymph node metastasis. Logistic regression was used to screen the risk factors of breast cancer lymph node metastasis. R software was used to construct the nomogram model of breast cancer lymph node metastasis, and the nomogram model of breast cancer lymph node metastasis was internally verified. Results Lymph node metastasis occurred in 50 of 155 patients with breast cancer, and the incidence of lymph node metastasis was 32.26% (50/155). Logistic regression analysis showed that vascular invasion, irregular morphology, calcification, SD, Emean and Emax were risk factors for lymph node metastasis of breast cancer (P<0.05). Based on the risk factors of breast cancer lymph node metastasis, a dynamic nomogram model was established. The actual probability of the correction curve of the nomogram model of breast cancer lymph node metastasis was consistent with the predicted probability. The area under ROC curve of the model was 0.899 (95%CI: 0.848~0.951). When the decision curve shows a threshold probability of 1% to 92%, the net benefit value predicted by the nomogram for breast cancer lymph node metastasis is higher. Conclusion Vascular invasion, irregular morphology, calcification, SD, Emean and Emax are risk factors for lymph node metastasis of breast cancer. The dynamic nomogram model of lymph node metastasis of breast cancer constructed has high accuracy and clinical practicability.