John Grogan (born March 20, 1957) is an American journalist and non-fiction writer. His memoir Marley & Me (2005) was a best-selling book about his family's dog Marley. He had been a reporter, bureau chief, and columnist for newspapers in Michigan and Florida before becoming the editor in chief of Rodale's Organic Gardening magazine. He was a columnist for The Philadelphia Inquirer. His next memoir, The Longest Trip Home, is scheduled for release on October 21, 2008.

He lives with his wife Jenny and their three children in rural eastern Pennsylvania. Grogan's dog Marley appeared in the movie The Last Home Run when he was on film for less than 2 minutes when a van pulls up to a curb and a girl steps out and a boy steps out with Marley.