Obesity is an escalating global pandemic posing a serious threat to human health.The intervention therapy using weight-reducing drugs,accompanied by lifestyle modification,is a strategy for the treatment of obesity.In the present study,we explored the role of fucoidan,a seaweed compound,on high-fat diet(HFD)-induced obesity in mice.We found that fucoidan treatment significantly reduced the body fat and caused redistribution of visceral and subcutaneous fat in HFD-fed mice.Meanwhile,fucoidan treatment inhibited adipocyte hypertrophy and inflammation in adipose tissue.Collectively,these results suggest that fucoidan may be a promising treatment for obesity and obesity-induced complications.