Objective: To investigate the expressions of tight junction protein claudin-1 (Cldn-1) and E-cadherin (E-cad) in breast cancer tissue and their relations with invasion and metastasis of this cancer. Methods: The expressions of Cldn-1 and E-cad in the breast cancer samples (n=77) were detected by using tissue chip technology and immunohitochemisty. The relations of Cldn-1 and E-cad with lymph node metastases, TNM stage, maximum lump diameter and histological classification of breast cancer were analyzed. Results: The expression intensities of Cldn-1 and E-cad were associated with lymph node metastases and clinical stage of breast cancer. The results showed that the expression intensities of Cldn-1 and E-cad in the breast cancer tissues with nodal metastases were significantly lower than those without lymph node metastases (P=0.0009, P=0.014), the expression intensity of Cldn-1 in stage III breast cancer was significantly lower than that in stage I and stage II (P=0.046, P=0.047), and the expression intensities of E-cad in both stage II and stage III breast cancer were significantly lower than that in stage I (P=0.021, P=0.001). The expression intensities of Cldn-1 and E-cad were unrelated to the maximum lump diameter and histological classification of the tumor (P=0.967, P=0.150 and P=0.188, P=0.164). There was no significant difference between the expression intensities of Cldn-1 and E-cad in breast cancer (P=0.747). Conclusion: Both Cldn-1 and E-cad expressions show a decreasing trend in development and metastases of breast cancer, but both may be independent factors. Combination measurement of Cldn-1 and E-cad is of value for the screening of breast cancer with high risk of recurrence, and they may be potential indicators for metastases, recurrence and prognostic estimation of breast cancer.