Jack Hanna (born January 2, 1947 in Knoxville, Tennessee) is an American zoo keeper who is the Director Emeritus of the Columbus Zoo and Aquarium. He was Director of the zoo from 1978 to 1993, and is viewed as largely responsible for elevating its quality and reputation. His media appearances have made him one of the best known and well liked animal experts in the United States. Hanna, nicknamed "Jungle Jack", is instantly recognizable by his khaki safari outfit, deep tan, Southern twang, pseudo-serious delivery, and shaggy hair.

Hanna grew up on his father's farm outside Knoxville, and volunteered for a veterinarian when he was 11. He attended The Kiski School, an all-boys boarding school in Saltsburgh, PA for high school, graduating in 1965. He majored in business and political science at Muskingum College in New Concord, Ohio, where he got in trouble for keeping ducks in his dorm room and a donkey in a shed behind his fraternity house (The M.A.C.E. Club). His senior year, Hanna married Suzi, a cheerleader at Muskingum, and graduated in 1969. Though unable to secure zoning as a zoo for his father's farm, the two opened a pet shop and petting zoo. In 1973, a three-year old boy was mauled by a lion at Hanna's farm and lost his arm. Hanna settled the subsequent lawsuit out of court, shut down the petting zoo, and moved his family to Florida . He then worked for a wildlife adventure company and directed the small [Central Florida Zoo] from 1973 to 1975. When he was offered the position at the Columbus Zoo in 1978, one of the reasons why he accepted was because he believed Children's Hospital in Columbus had the best treatment available for his daughter Julie's leukemia. She recovered by the age of six, though she needed a brain tumor removed later in life.

At the time he became the zoo's director, the grounds of the zoo were unkept and the facilities rundown. Hanna initially struck many as a "zealous" zoo director, often traveling around the zoo grounds after closing to personally pick up trash. He also realized the importance of increasing the profile of the Columbus Zoo in central Ohio to garner more public support and funding, and the everyman-seeming Hanna proved to be very well suited to public relations for the zoo. From 1981 until 1983, Hanna hosted a television show called Hanna's Ark that aired on the local CBS affiliate in Columbus, WBNS. Hanna's live animal demonstrations on Good Morning America and both of David Letterman's talk show incarnations brought national attention to the Columbus Zoo as well as to Hanna himself. Over the course of Hanna's tenure as director, the zoo made the transition from cage-like enclosures to habitat environments, and the grounds were significantly expanded. The annual attendance of the Columbus Zoo increased by over 400% during this time.

Hanna has published an autobiography, Monkeys on the Interstate (1989), as well as many other books for children. He has been the host of the syndicated television show Jack Hanna's Animal Adventures since 1997. Hanna also occasionally contributes commentary as an animal expert on various local and national news programs, and has done guest spots on other shows such as Larry King Live, Nancy Grace, and Hollywood Squares. He was also named one of the "50 most beautiful people" by People magazine. Hanna also appeared in Neal McCoy's 2005 music video for "Billy's Got His Beer Goggles On" with a Hyacinth Macaw, a sloth and an albino burmese python.

Hanna and his wife, Suzi, have three daughters: Kathaleen, Suzanne, and Julie. He spends much of his time at his home in Montana, where he expects to retire soon. Hanna has been granted honorary Ph.D.s from Muskingum College, Otterbein College in Westerville, Ohio, and Capital University in Columbus, Ohio.