The survey was conducted by fashion website My Celebrity Fashion. Law topped the list for his "formal look and well-groomed appearance".
Johnny Depp came in second and David Beckham was named third.
Robert Downey Jr and musician Gavin Rossdale also appeared on the list, as well as director Guy Ritchie, Matthew McConaughey, Will Smith and Jamie Redknapp.
Jack Black and Jonathan Ross were among the worst dressed celeb dads named.