Bob, Bobby or Robert Mann may refer to:

• Bob Mann (American football) (1924–2006), American football player
• Bob Mann (golfer) (born 1951), American golfer
• Bobby Mann (born 1974), Scottish footballer

• Bob Mann (Canadian politician), Ontario Communist Party candidate
• Bob Mann (guitarist) (born 1944), American guitarist/keyboardist
• Robert Mann (1920–2018), musician
• Robert Mann (Royal Navy officer) (1748–1813), British admiral
• Robert James Mann (1817–1886), English physician and science writer
• Robert Trask Mann (1924–2002), American judge and politician in the Florida House of Representatives
• Robert Wellesley Mann (1924–2006), pioneer in the field of medical prosthetics
• Robert E. Mann, member of the Illinois House of Representatives