This project I will attemt through the systems and personnel matters of ”Kao-Gong-Yuan-Wai-Lang” to confer their family background and promote ways during the Pre-Tang Dynasty. Further, I will try to through the styles and behaviors of the Zhi-Gong-Ju, to find out whether through the procession of the examination can accomplish the talent's selection, or promotion the social mobility? Or it still remains the family of power and influence, therefore, the promotion of social mobility is not obvious?