Koch (German: "cook") may refer to any of the following people:

• Bill Koch - cross-country skier
• Billy Koch - Major league baseball relief pitcher
• Carl Ludwig Koch and his son Ludwig Carl Christian Koch - German entomologists specializing in arachnology
• Carl Wilhelm Otto Koch, (1810 - 1876), mayor of Leipzig
• Charles G. Koch - Billionaire, heir and CEO of Koch Industries and co-founder of the free-market Cato Institute.
• Christof Koch
• David Koch (analyst) - Australian financial analyst and TV presenter
• David H. Koch - Billionaire, 1980 Libertarian Party Vice-Presidential candidate, heir to Koch Industries.
• Dorothy Bush Koch
• Edward I. Koch - former Mayor of New York City
• Erich Koch - Gauleiter of East Prussia
• Fred C. Koch - Founder of Koch Industries, and supporter of the John Birch Society.
• Hagbard Karl Koch, a German hacker in the 1980s
• Heinrich Christoph Koch German musicologist, author of Versuch einer Anleitung zur Composition
• Helge von Koch - Swedish mathematician, originator of the eponymous Koch snowflake
• Howard Koch
• Ilse Koch - wife of Karl, "The Bitch of Buchenwald"
• Joseph Anton Koch (1768 - 1839), Austrian painter
• Karl Koch - German botanist
• Karl Koch - German film director and writer
• Karl Otto Koch - the first commandant of Buchenwald
• Ludwig Carl Christian Koch (1825 - 1908) - German entomologist and arachnologist
• Marita Koch - sprint athelete, born 1957
• Martin Koch - Swedish novelist
• Richard Koch
• Robert Koch - German physician, discoverer of the tubercle and cholera bacilli, Nobel Prize in Medicine laureate in 1905
  • Koch's postulates, formulated by Robert Koch
• Roland Koch - German politician
• Walter Karl Koch - a German surgeon
• Werner Koch
• William I. "Bill" Koch - America's Cup yachtsman, businessman, and son of Fred Koch

Koch may also be:

• Koch - A type of arctic boat
• Koch - A language spoken in India and Bangladesh
• Koch - a town in Texas
• Koch Entertainment, owner of Koch Records
• Heckler & Koch, maker of firearms
• Koch Industries - a chemical company