A US man has accidentally shot himself in the penis after trying to holster his wife's pink gun in the waistband of his pants.

Joshua Seto, who is recovering in hospital, was walking towards a grocery store with his fiancee Cara Christopher in Chandler, Phoenix, when the gun accidentally fired.

The bullet hit his penis before continuing through his left leg, the Daily Mail reported.

Police couldn't confirm what type of gun Seto has stored in his pants, or whether the weapon had a safety that was off.

In a second blow, the man could face charges for carrying the weapon.

Police were unable to confirm whether Seto had left hospital, or if he would have any long-lasting damage.

The incident served as a reminder of the dangers of guns, Chandler Police Detective Seth Tyler said.

"Whenever you handle a firearm, whether you are a novice or experienced, always treat firearms as though they are loaded. If you are going to carry a handgun on your person, use a holster, not your waistband," he said.