Robert or Bob Watt may refer to:

• Robert Watt (bibliographer) (1774–1819), Scottish physician and bibliographer
• Robert Watt (miner) (1832–1907), Scottish–American miner
• Robert Watt (officer of arms) (born 1945), Canadian museum curator and officer of arms
• Robert Watt (Irish civil servant), secretary general of the Department of Health (Ireland)
• Robert Lee Watt (born 1948), first African American French hornist hired by a major symphony orchestra in the United States
• Bob Watt (ice hockey) (1927–2010), Canadian ice hockey player
• Bob Watt (footballer) (1933–1984), Australian rules footballer