  We construct a cosmological model of late acceleration based on the new
agegraphic dark energy model in the framework of Brans-Dicke cosmology where
the new agegraphic energy density $\rho_{D}= 3n^2 m^2_p /\eta^{2}$ is replaced
with $\rho_{D}= {3n^2\phi^2}/({4\omega \eta^2}$). We show that the combination
of Brans-Dicke field and agegraphic dark energy can accommodate $w_D = -1 $
crossing for the equation of state of \textit{noninteracting} dark energy. When
an interaction between dark energy and dark matter is taken into account, the
transition of $w_D $ to phantom regime can be more easily accounted for than
when resort to the Einstein field equations is made. In the limiting case
$\alpha = 0$ $(\omega\to \infty)$, all previous results of the new agegraphic
dark energy in Einstein gravity are restored.
