We argue that a country’s position in preferential trade agreements (PTAs) network affects its global value chain (GVC) participation level through two opposite effects: the resource allocation effect, which promotes the GVC participation level, and the market substitution effect, which decreases it. Using data from 43 countries over the 2000–2014 period, we find that the overall centrality of a country's position in the ego-centered PTAs network is positively associated with its GVC participation with other member countries, suggesting that the resource allocation affect dominates the market substitution effect. However, upon decomposing the PTAs network into private and common networks, we find that the centralization of a country's position in the private PTAs network has a negative effect on its GVC participation. In contrast, the centralization of a country's position in the common PTAs network has a positive effect on its GVC participation. Furthermore, the centralization of the private network weakens the effect of individual deep PTAs on bilateral GVC participation, while the centralization of the common network strengthens the effect of individual deep PTAs on bilateral GVC participation. A series of tests confirms the robustness of our main findings.