Robert Earl Hughes (June 4, 1926 – July 10, 1958) was, during his lifetime, the heaviest human being recorded in the history of the world. Hughes' excessive weight was attributed to a malfunctioning pituitary gland. His chest was measured at 3.15 metres (10.3 ft), and he weighed an estimated 486 kilos (1,070 lb) at his heaviest. At the age of six, he weighed about 92 kilos (200 lb); at ten, he weighed 171 kilos (380 lb). By the time of his death, he weighed over half a ton.

During his adult life, Hughes made guest appearances at carnivals and fairs; plans to appear on the Ed Sullivan television program were announced but never came about. On July 10, 1958, Hughes contracted a case of measles which soon developed into uremia, resulting in his death in Baylis, Illinois, U. S.; he was 32 years old.

He is often said to have been buried in a piano case. This error stems from a sentence that appeared in successive editions of the Guinness Book of World Records, which read, "He was buried in a coffin the size of a piano case." His headstone notes that he was the world's heaviest man at a confirmed 1,041 pounds (472 kg).