Objective To investigate the characteristics of contrast-enhanced ultrasound findings and their relationship with tumor suppressor gene P53 and cytokeratin 5/6 (CK5/6) in patients with triple negative breast cancer (TNBC).Methods A total of 98 TNBC patients (TNBC group) and 103 patients with other types of breast cancer (NTNBC group) who underwent breast contrast-enhanced ultrasound in the Department of Ultrasound of The First Affiliated Hospital of Nanjing Medical University from July 2014 to June 2020 were selected. All patients received surgical treatment, and the expression of P53 and CK5/6 was detected by immunohistochemistry in the breast cancer tissues of TNBC patients resected during the operation. Besides, we analyzed the characteristics of two-dimensional ultrasound and contrast-enhanced ultrasound signs and their relationship with the expression of P53 and CK5/6 in patients with TNBC.Results In TNBC group, the proportions of masses with regular contours, posterior echo enhancement, and grade Ⅱ and Ⅲ blood flow were higher, while the proportions of ill-defined masses and those with microcalcification were lower compared with NTNBC group (P < 0.05). The diameter and length-to-width ratio of the masses were not different between the two groups (P > 0.05). In addition, the masses of TNBC group in the contrast-enhanced ultrasound were tended to exhibit high enhancement, inhomogeneous enhancement and modest enlargement with filling defects (P < 0.05). There was no difference in the presence of perforator vessels between the TNBC group and NTNBC group (P > 0.05). The positive expression rate of P53 in patients with grade Ⅱ and Ⅲ blood flow was greater than that in patients with grade 0 and Ⅰ blood flow, whereas the positive expression rate of CK5/6 was higher in patients with well-defined masses than that in those with ill-defined masses (P < 0.05). Compared with patients with masses of equal, low or no enhancement, those with masses of high enhancement showed a lower positive expression rate of P53 (P < 0.05). Moreover, a higher positive expression rate of CK5/6 was observed in patients with masses that were modestly enlarged relative to those with masses that were obviously enlarged in the contrast-enhanced ultrasound (P < 0.05).Conclusions Contrast-enhanced ultrasound signs of TNBC are significantly different from those of NTNBC, and the expressions of P53 and CK5/6 are correlated with contrast-enhanced ultrasound signs of TNBC to some extent.