For the wavelength division multi-access system (WDMA), the reservation approach and the pre-allocation approach are two major media access protocols to support the packet-switched traffic. In this paper, a new media access control (MAC) protocol, the AP-WDMA (accelerative pre-allocation), is proposed for the WDMA. Although implemented on a simple basic architecture, it does provide a better media access protocol which can be easily extended to all the WDMA's. Through evaluations, the AP-WDMA is shown to be able to overcome the wavelength limitation through channel sharing mechanism and enable efficient transmission with the accelerative mechanism. The AP-WDMA relieves these technology constraints by restricting the tunability to only one end and the table size to only n+2 memory spaces, where n is the number of stations.