For many contemporaries, the twentieth century was an age of the Holy Spirit. Besides the great revivals in Wales, India, and Korea, the enthusiasm of the Keswick Convention was also carried by the missionaries to China. For Chinese Protestants, pneumatology is an understudied doctrine, even though many desperately desired the Holy Spirit’s power. While praying for the Spirit’s guidance and teaching the importance of spiritual disciplines (ling xiu 靈修), very few in the Republican era systematically wrote about the Holy Spirit. This paper examines Marcus Cheng’s (陳崇桂) pneumatology in light of the spread of Keswick spirituality in early twentieth-century China and the Chinese pneumatological traditions. Special attention will be paid to Cheng’s Studies of the Holy Spirit (聖靈之研究, 1933). By examining Cheng’s pneumatology in contrast to other Chinese writers, such as Jia Yuming (1880–1964), Watchman Nee (1903–1972), and Wang Mingdao (1900–1991), this paper looks into Cheng’s contribution to the development of Chinese evangelical theology.