The purpose of this study was to determine average penile length and to investigate the relationship between penile length and somatometric parameters in a group of young, healthy Turkish men. A total of 1,132 men were included in the study. The age, height and weight of the subjects were recorded. Penile length was measured in both flaccid and stretched states. The correlation between penile length and somatometric parameters was analysed. The mean age of the subjects was 20.3±0.9 years. The mean penile length in flaccid and stretched states was 9.3±1.3 and 13.7±1.6 cm, respectively (P<0.001). There was a positive correlation between flaccid and stretched penile length (r=0.800, P<0.001). The mean testicular volume was 22.0±2.8 cm(3). A weak positive correlation was detected between penile length and mean testicular volume (r=0.143 for flaccid penile length and r=0.140 for stretched penile length, P<0.001 for both). Similarly, weak positive correlations were found between penile length (both flaccid and stretched) and height, weight and body mass index, respectively (P<0.001, for all). These results demonstrate that somatometric parameters are correlated with penile length. We believe that further studies would provide more information about the causal relationship.