The Hidden Prince of Oz is a novel written by Gina Wickwar and illustrated by Anna-Maria Cool. As its title indicates, the book is an entrant into the series of Oz books by L. Frank Baum and his many successors. The publication of the book was timed to coincide with the centennial of the original Oz book, The Wonderful Wizard of Oz (as was also true of Edward Einhorn's Paradox in Oz and Dave Hardenbrook's The Unknown Witches of Oz). It was the winner of the Club's Centennial book contest, which received over 100 entries in 1998.