Briefly compare the polarization rotation speed of Mach-Zehnder interferometer, lithium crystal, LCD and semiconductor optical amplifier (SOA), etc. Then propose a program of high-speed ternary optical multiplier based on SOA’s nonlinear polarization rotation. Finally, the theoretical analysis and simulation research of SOA’s nonlinear polarization rotation indicate that the ternary optical multiplier is one of the possible options to achieve high-speed optical computing, and may be widely applied to optical computer.