Abstract Background Breast cancer is a leading cause of death and disability between women, particularly young women, in low- and average -income countries (Porter, 2018). Neoadjuvant chemotherapy (NAC) is increasingly used in management patients with locally advanced breast cancer (LABC) (Mougalian et al., 2015). Mammography and breast ultrasound are the most widest diagnostic techniques used to evaluate primary tumor size and character at the time of diagnosis and monitoring the response to NAC (Kald et al., 2015). Aim of the work The purpose of this study is to assess and evaluate the role and the accuracy of Mammography and breast ultrasound modalities in monitoring the response of the breast cancer to the neoadjuvant chemotherapy. Patients and methods Twenty three patients presenting with pathologically proven malignant mass and conducted for neoadjuvant chemotherapy with age above 40 years-old. They were referred to the radiology department (mammography unit, Ultrasound unit and MRI unit) at El Salam oncology center, during the period between December 2018 to June 2019. Once a patient satisfied the inclusion and exclusion criteria for this study, an elaborate history was taken from all the patients which was followed by a thorough clinical evaluation, in which duration of symptoms, affected side, affected breast and family history. Patients were subjected to evaluation before starting neoadjunant chemotherapy by mammography, ultrasound and MRI as well as after finishing the neoadjuvant cycles which usually was ranging 3-4 cycles. Results Total of 23 patients with breast cancer were enrolled in this study. The patients were in the age group of 41-70 years with mean age of 54 years. Majority of patients had infiltrative ductal carcinoma IDC (16 cases -69.56% and the rest of cases were infiltrative lobular carcinoma (9 cases -39.13 %). After monitoring the response of the cases to neoadjuvant chemotherapy the results showed significant regressive course to the majority of cases ( 17 cases ) (73.91%) with the rest non respondent cases divided to cases with stationary ( 3 cases ) (13.04% ) and cases with progressive course ( 3 cases ) (13.04% ). The comparison between the results of Sonomammographic assessment of the breast lesions before and after the neoadjuvant chemotherapy cycles and also to MRI show close results. There were 5 cases that showed non-respondent (including stationary course and progressive course) in both Sonomammography and MRI and only one case that was respondent according to Sonomammography and non-respondent according to MRI breast (false +e). On the other hand there were 16 cases that had showed respondent fashion in both Sonomammography and MRI. Also there was one case that had showed non-respondent course according to Sonomammography and was respondent according to MRI results (false –ve). Sonomammography sensitivity was 94.12 % and specificity was 83.33% compared to MRI results, with high accuracy value reaching to 91.30 %. Conclusion The ability of mammography and breast ultrasound to accurately measure residual tumor size following neoadjuvant chemotherapy compared to Breast MRI measurement of the residual tumor demonstrated sensitivity of 94.12 % and specificity of 83.33% with high accuracy value reaching to 91.30 %. Even that the MRI is proved to be of high accuracy in detecting residual tumor, sonomammographic imaging isa cost-effective imaging modality than the MRI with sensitivity and specificity near to that of MRI.