London police said Constables Helen Hansen and Dave Kadwell spotted the hamster being chased by a cat in the Beddington neighborhood and waved their arms to ward off the feline, The Mirror reported Monday.
The constables chased the rodent until Hansen was able to trap it under a helmet.
Police said the officers knocked on the door of a nearby home after noticing a "beware of hamster" sign in a window.
"Until they knocked on the door, we didn't know he was missing," said Debbie Rook, mother of hamster owners Milly, 8, and Bradley, 11. "I can't believe a hamster survived a drop like that. We're grateful to the police for coming to the rescue."
The family said Rolo the hamster must have jumped from a window to begin his adventure.