Abstract： Objective To investigate the association between obesity and benign prostate hyperplasia (BPH).Methods A total of 253 men (>40 year old) with no obesity related diseases were selected.Medical history,height,body weight,waist circumference (WC),body fat ratio,blood pressure,fasting blood glucose,blood lipid and prostate ultrasound were evaluated.The participants were then assigned to the normal group (body mass index 18.5 to 23.9 kg/m2),overweight group (24.0 to 27.9 kg/m2) and obesity group (≥28 kg/m2).The subjects were also divided into the normal group (WC<85 cm) and abdominal obesity group (WC≥85 cm) or normal group (body fat ratio≤25%) and excessive body fat ratio group (>25%).Prostate volume was analyzed in each group.Results The prostate volume was significantly different between the normal body mass index group and overweight or obesity groups,normal WC group and abdominal obesity group,and normal body fat ratio group and excessive body fat ratio group.The prostate volume was increased in individuals with higher body mass index,WC and body fat ratio.Of those with body mass index≥24 kg/m2 and normal WC or body fat ratio,the incidence of BPH was not significantly increased.Conclusion Obesity may be a risk factor for BPH; individuals with increased WC and body fat ratio may have a higher risk of BPH.