As a cutting‐edge technology with characteristics of transparency, traceability, decentralization, and immutability, blockchain technology (BCT) has been thought as an effective method of enhancing green supply chain integration (GSCI). However, the mechanism of how BCT affects GSCI is still blurred. Based on transaction cost theory and resource dependence theory, this research explores the mediating effect of supply chain trust in the relationship between BCT adoption and GSCI and the moderating role of organizational culture. We examine hypotheses using two waves of survey data from 317 Chinese manufacturers. The results reveal that BCT has a positive effect on supply chain trust, and supply chain trust partially mediates the impacts of BCT on three dimensions of GSCI. Moreover, a flexible‐oriented culture alleviates the impact of BCT on supply chain trust, whereas a control‐oriented culture strengthens the relationship. This research unfolds the “black box” in the BCT–GSCI relationship by exploring the mediating role of supply chain trust, and it is seldom a study that simultaneously combines information management area (BCT), operation management area (GSCI), and organizational behavior area (organizational culture) in a framework.