Aiming at the problem of complexity and inflexibility of image sampling control in the video image collection technology today,a method of realizing I2C bus interface by VHDL technology is proposed in this paper. This method based on the available video sampling chip SAA7111 can be used for control video collection processor to collect video image. The experiment indicates that I2C bus can control SAA7111 to sample image data correctly and steadily. This scheme is well transplantable.