To investigate expression of connexin43 (Cx43) and E-cadherin (E-cad) and its relationship with the biological behavior in Laryngeal carcinomas.Immunohistochemistry staining (PicTure two steps method) was used to detect connexin 43 and E-cadherin expression in 60 paraffin-embedded laryngeal carcinomas and 10 normal epithelia around tumors. All the patients were followed up more than five years.Cx43 and E-cad were expressed by normal epithelia with typical membranous staining 10 normal epithelia strongly expressed Cx43 and E-cad. The reduction rate of Cx43 expression in laryngeal carcinomas was 30.0%. The significant relationship was observed between low Cx43 expression and differentiation, lymph node metastasis and recurrence (chi2 = 15.09, 6.41, 3.86, P 0.05). 41.7% laryngeal carcinoma showed reduced or no expression of E-cad. Tumor cell dedifferentiation correlated with reduced expression for E-cad (chi2 = 15.07, P < 0.01). Absent or low E-cad expression was observed more frequently in patients with local recurrence and lymph node metastasis and with less than 5-year survival period (chi2 = 5.35, 6.65, 5.14; P < 0.05, 0.01, 0.05). There was a positive relationship between the expression of Cx43 and E-cad in same sample (r = 0.63, P < 0.0001).Laryngeal cancer presented inactivation of Cx43 gene and E-cad gene and down regulation of Cx43 and E-cad proteins. The level of Cx43 and E-cad may be a sensitive predictor of differentiation, invasion, lymph node metastasis and recurrence. E-cad is also a prognostic factor for patients with laryngeal cancer.