In order to realize one-to-many and many-to-many communications for optical waveguide matrix switch,a new type of optical waveguide matrix switch was designed.Two switch units were defined on analysis of the basic structure of Mach-Zehnder Interferometer (MZI).Then,based on this two units,the new structures of 2×2 and 4×4 optical matrix switches were proposed to realize the multiport interconnection of 1∶k(k>1).The influences of the intersection angles among waveguide links on the intersection-induced optical loss of system were studied in Banyan network and the total insertion losses of system were discussed after the performance simulation and the optimization of MZI construction.Finally,SiO₂-based MZI units,2×2 and 4×4 optical matrix switches were fabricated based on Planar Lightwave Circuit (PLC) technology.The experimental results indicate that the insertion losses of 2×2 optical matrix switch and 4×4 optical matrix switch are 2.25 dB and 4.3 dB,respectively,and the response time is less than 1 ms.It concludes that this type of optical switch can primely fulfill the multiport switch function.