This paper has reported the research of a scalable wavelength division multiplexing (WDM) optical routing system applied to the interconnection between CPU and MEM of distributed parallel computer. This system is built on DWDM and the optical switch array, which can connect CPUs and MEMs in a multigigabit WDM fiber, and so take advantage of high throughput, low-latency, error-free parallel transmission. And the paper has analyzed the performances degradation arising from super-speed and multi-wavelength, and put forward practical improvement measures. Furthermore the paper has designed a dual-window DWDM experimental system, and tested the data exchange between CPU and MEM. The purpose of this paper lies in exploring an optical WDM interconnection routing system which can not only be super-capacity, and reduce the complexity in implementation technologies, and also optimize the internal structures, or even external communication mechanisms of parallel computer.