In this paper, a wavelength adaptive assignment scheme called CExF (collision-evaluated adaptive fit) has been proposed for Optical Transport Network in Intelligent Highway to solve the date intensive scheduling. CExF assign a limited and more accurate weight, where the weight denotes the concurrent reservation probability, and the destination can select a wavelength with less collision probability by a new adaptive wavelength assignment according to the weight. Simulations show that CExF performs better in backward blocking, and even in forward blocking under medium traffic loads.