The influence of the cell cycle profile and the site of the primary tumour on the overall survival were examined in 36 patients with squamous cell carcinoma of the larynx. DNA ploidy (p = 0.0091), the overall proliferative activity (p = 0.0001), the overall proliferative activity of diploid tumour cells (p = 0.0017) and primary tumour site (p = 0.0008) were found to be significant single prognostic factors of the overall survival. Multivariate analysis showed that only the overall proliferative activity was prognostically significant (p = 0.013). The results of the study show that the supraglottic site of the tumours correlates significantly with DNA ploidy (p = 0.0334) and the overall proliferative activity of tumour cells (p = 0.0159), whereas the correlation with proliferative activity of diploid tumour cells (p = 0.1416) has not been confirmed by this study. Glottic tumours showed a prognostically significant correlation with the overall proliferative activity (p = 0.0037) and proliferative activity of diploid tumour (p = 0.0054). Such a prognostic correlation was not found for DNA ploidy (p = 0.6542).