The Land Before Time IX: Journey to Big Water is a 2002 direct-to-video animated adventure musical film and the ninth film in The Land Before Time series. It was produced and directed by Charles Grosvenor. This is also the last film to use the soundtrack composed by James Horner. During the year this was released, Universal brought back on DVD, for the first time, two of the previous The Land Before Time films: The Great Valley Adventure and The Time of the Great Giving.

When heavy rains create a mysterious "new water", Littlefoot sets off to explore the Great Valley. He quickly becomes friends with Mo the mischievous Ophthalmosaurus who has been isolated from his pod by the weather. When Littlefoot and friends get separated from their parents because of an Earthshake, they help Mo get back home to the Big Water, while avoiding a hungry "Sharptooth Swimmer". On the way, Littlefoot and Mo discuss such interesting and see dangerous things like imaginary friends, the Sharptooth Swimmer, the concept of loneliness, and the true meaning of a brother.