Blockchain technology (BCT) can alleviate information asymmetry between banks and enterprises while enhancing product traceability in dual-channel supply chains. Considering both the mitigation of information asymmetry and market potential incentives offered by BCT, this paper constructs a game model of the capital-constrained dual-channel supply chain consisting of a manufacturer, a retailer, and a bank. The equilibrium decisions and profits of each participant in the two scenarios: No BCT adoption (Scenario N) and with BCT adoption (Scenario T)are derived. Further, the impact of BCT adoption on the retailer’s financing environment and the equilibrium results are obtained through comparative analysis. Several findings are obtained: First, BCT can improve the financing environment for the retailer by reducing financing gaps and costs. Second, the market potential incentive effect of BCT positively affects all participants, as it allows for increased market potential in both channels. Third, the information asymmetry mitigation effect does not positively affect all participants: It is always favorable to high-quality retailers and banks, while it is always unfavorable to low-quality retailers. It is favorable to the manufacturer only when the retailer’s own capital is relatively large. Finally, smart contracts can help the bank avoid moral hazard and further boost the positive effects of information asymmetry mitigation on both the high-quality retailer and the bank. The findings may have implications for BCT adoption decisions to facilitate inclusive finance and supply chain traceability.