One challenge faced by Chinese Catholicism in early twentieth-century China was how to negotiate relations with other religions. In an environment where Catholic presence was often tied to the appearance of Western imperial powers, interreligious relations were prone to become tense. Therefore, the ways a Buddhist monk has seen Catholicism in this period can provide intriguing insights regarding the extent to which Catholics in China could manage these relations. The present paper will focus on the texts of Buddhist Master Taixu 太虛大師, who was one of the leading reformers of Buddhism at the time and maintained close relations with foreign missionaries, as well as Chinese Christians. In his early writings, he was starkly critical of Christianity, blaming it even for the outbreak of the First World War. Nevertheless, by 1943, he co-founded the Association of Chinese Religious Believers with Cardinal Paul Yu Bin 于斌主教 among others. What happened during those thirty years? How did Taixu's understanding of and approach to Catholicism change? What can this tell us about Catholicism in China during this time? The paper will provide answers to these questions by drawing on the speeches and writings of Master Taixu.