The Rock just bought his housekeeper a new car ... we're going out on a limb concluding it's his housekeeper, but we have evidence.

-- The top-grossing actor of 2013 says, "For 10 yrs she's cared after our homes with the love of a mama & an eagle's eye. Just surprised, Esperanza with a new ride!#WeLoveU"

-- Some people in our office say the bandana and sweatpants are also clues. Others think it has no relevance whatsoever.

Either way ... Esperanza scored a Ford Edge.