This article discusses the interrelations between different episodes of contention in China through a case study of the Maoming anti-PX protests in 2014. Drawing on interviews and documentary data, the author specifies the spillover effect of previous anti-PX activism on the Maoming case. This article argues that preceding anti-PX protests helped bring about the Maoming protests, and explains how diffusion shaped protest dynamics in two aspects. First, it shows how local officials reacted to previous anti-PX episodes by taking pre-emptive measures designed to prevent mobilization in Maoming. However, this strategy backfired. Instead, it directly contributed to the anti-PX protests by facilitating cognitive liberation and activist networking. Second, this article shows how Maoming contenders also underwent a learning process. Previous anti-PX protests exerted an influence on the grievance framing in the Maoming protests and encouraged mobilization by increasing public expectations for success and legitimizing protest as a tactic. During the course of contention, Maoming protesters actively drew on their predecessors’ experiences, which shaped their own strategies accordingly.