It saw off competition from three other short-listed books: Catherine Fisher's The Oracle; Michael Morpurgo's Private Peaceful and Jeanne Willis' Naked Without A Hat.
David has now received the award twice. He first won for Skellig in 1998.
Mark and David each received £5,000 for scooping their awards.
They will now go on to compete against three other category winners for a top prize of £25,000.