male or female? assuming you do not have any infection (vaginal skin etc. ) or poor hygiene habits the best way to reduce groin odor is to control odor-causing bacteria and sweating. use a good antibacterial soap. shower often up to twice a day if you need. wear clean fresh underwear daily. for men consider boxers over tighty-whiteys. for women use cotton undies that "breathe" better even though these granny-panties may not be the most attractive girlie thing to choose. if all fails see your medical provider to see if there is an underlying medical reason for the odor issue.
how can i prevent and treat groin odour?