The basketball player was travelling through Minneapolis - St. Paul Airport and had to remove the band to go through a security checkpoint, but dropped the ring after walking through the metal detector.
A fan quickly spotted the mishap, grabbing the ring and chasing after Humphries to hand back the prized item, according to TMZ.
The sports star then happily posed for a picture before continuing his journey.
The wedding band was made by jeweller Lorraine Schwartz and cost $10,000 (£6,250).
Humphries married the reality TV socialite in California in August (11).