Ian Stewart may refer to:

• Ian Stewart (musician) (1938-1985), British musician and early member of the Rolling Stones
• Ian Stewart (racing driver) (born 1929), Scottish Formula One driver
• Ian Stewart, Baron Stewartby (born 1935), British Conservative Party politician former MP for Hitchin, England
• Ian Stewart (Australian rules footballer) (born 1944), member of the Australian Football Hall of Fame
• Ian Stewart (mathematician) (born 1945), English academic and science fiction author
• Ian Stewart (athlete) (born 1949), Scottish Olympic athlete
• Ian Stewart (Labour politician) (born 1950), Scottish politician
• Ian Stewart (baseball) (born 1985), major league baseball player
• Ian Stewart (Northern Irish footballer), member of the 1986 Northern Ireland Football World Cup team
• Ian MacAlister Stewart, brigadier general during the Second World War
• Ian Stewart (Royal Air Force officer), current United Kingdom National Military Representative, Supreme Headquarters Allied Powers Europe (UK)
• Ian Stewart (diplomat), former New Zealand ambassador to Belgium, Italy and Thailand
• Ian Duncan Stewart or Ian Brady (born 1938), British serial killer and author
• Ian Stewart, founder of Gremlin Interactive and Zoo Digital

[ Source: Wikipedia ]