Garretson may refer to:

• Garretson (surname)
• Garretson, South Dakota
• Garretson W. Gibson (1832–1910), President of Liberia

• KATU.com
• Katu (disambiguation)
• Katugampola Electoral District
• Katuginskoy mine
• Katuheng
• Katuhing
• Katu'iyeh
• Katuiyeh
• Katuka
• Katukan
• Katukan, Iranshahr
• Katukina do Acre language
• Katukina do Jurua language
• Katukina do Juruá language
• Katukina-Kanamari language
• Katukina languages
• Katukina Pano language
• Katukinaru language
• Katukinarú language
• Katukína-Kanamarí language
• Katukínan languages
• Katul
• Katula
• Katu language
• Katulpur