Is it true that all his novels are based on his own life?

His novels aren't so much based on his life as they are inspired by events in his own life, and though that goes for most of his work, it doesn't apply to all of his books. For instance, his sixth novel, Nights in Rodanthe, was entirely fictional. For a further discussion, please see links to specific novels: The Notebook, Message in a Bottle, A Walk to Remember, The Rescue, A Bend in the Road, Nights in Rodanthe, The Guardian, and The Wedding.