This paper focuses on using FPGA board to realize the ability of vocabulary recognition for humanoid robot. At first, the system structure of the humanoid robot system is setup. The central process unit of the humanoid robot is a FPGA board, ALTERA Nios II EP2C20F324C8, which not only controls all the motors of robot but also processes the information of vision system. The vocabulary recognition method is then introduced. We apply the image segment to find the valid region, and use the encoding method to sample the word. After matching algorithm, we use a speech module, Emic TTS module, to pronounce the word. Finally the experiments verify the procedure of the proposed module and demonstrate the feasibility of the vocabulary recognition and speak out function for the humanoid robot.