Eunuch interference in political affairs was one of the key factors influencing the rise and fall of Chinese dynasties. It is generally believed that Qing emperors ordered the Imperial Household Department to totally manage the internal court affairs in order to eliminate the disadvantages of eunuch interference. Eunuchs appeared along with imperial power, just as maggots in bone, so this phenomenon could not be fundamentally eliminated by the autocratic court. While it is true that throughout the whole Qing period, there was no disaster caused by the eunuchs, but there were many powerful and influential eunuchs during that time. Liang Jiugong was one of the henchman eunuchs of the Kangxi emperor, and he had close ties to parties to the succession dispute between Kangxi and Yongzheng ruling periods. This paper investigates his whole life by studying the relevant archives. Through focusing on the case of Prince Yincheng's abolition in 1712, it can be disclosed that Liang Jiugong secretly helped the prince to collude with the bold, marauding heroes living out in the green wood; that was not tolerated by the Kangxi emperor, and so he was imprisoned in Changchun Garden. After Yongzheng ascended the throne, Liang's home was raided, and he was forced to commit suicide. Meanwhile it was disclosed that he had had contacts with the ministers and amassed a huge fortune. Liang Jiugong was not only a well-known eunuch, but also an active person in court political affairs. This finding is helpful for getting rid of the traditional impression that the Qing dynasty had no powerful eunuchs, and can further deepen the study of the political history of the Qing dynasty.