This study compared the levels of signal transducer and activator of transcription 3 (STAT3) and cyclin D1 protein in paired primary and recurrent astrocytic tumours, and analysed their correlation with clinicopathological and treatment factors. A total of 48 samples from 24 patients who had undergone surgical removal of primary and recurrent astrocytic tumours were analysed. Levels of STAT3 and cyclin D1 protein were detected using immunohistochemistry. Increased STAT3 and decreased cyclin D1 levels were observed in recurrent astrocytic tumours compared with their paired primary tumours. There was a significant correlation between higher levels of STAT3 protein and shorter progression-free survival in primary tumours after surgery (r = 0.417), and a significant correlation between decreased cyclin D1 protein levels and radiotherapy in recurrent tumours (r = 0.468). It was concluded that increased STAT3 and decreased cyclin D1 protein levels may contribute to the recurrence of astrocytic tumours. Detection of STAT3 may be useful in predicting progressionfree survival in primary astrocytic tumours after surgery. In addition, radiotherapy may decrease cyclin D1 levels in astrocytic tumours, but the nature of this association requires further investigation.