In recent years, the real economy has suffered significant blows owing to the COVID-19 pandemic, leading to subtle changes in people’s consumption habits. In the economic environment influenced by the pandemic, “live-streaming e-commerce,” as an emerging business model, has become a crucial means for enterprises to achieve digital transformation. Therefore, in the online market, several brand manufacturers adopt a dual-channel operation strategy involving both direct and influencer’s live-streaming sales. Although consumers often enjoy discounts when shopping using live-streaming channels, the objective existence of the free-riding effect has resulted in the transfer of demand from the live-streaming channel to the direct sales channel.Considering this, we integrated the emerging online distribution method of influencer’s live-streaming for product sales into the operational decision-making and coordination issues of a dual-channel supply chain. Specifically, we considered brand manufacturers simultaneously operating direct and live-streaming channels. Moreover, brand manufacturers could choose between top-tier and ordinary influencers for live-stream sales. First, in decentralized and centralized scenarios, we derived the equilibrium pricing and live marketing efforts for dual-channel supply chain members. Subsequently, we performed comparative and sensitivity analyses of these equilibrium results. Finally, we proposed a “cost-sharing and two-part tariff” joint contract to coordinate the dual-channel supply chain and achieve a win-win situation for both the brand manufacturer and top-tier (ordinary) influencer.First, we examined two decentralized scenarios, denoted as scenarios ds and dn, which represent live-streaming sales by top-tier and ordinary influencers, respectively. In scenario ds, the top-tier influencer holds a dominant position with the brand manufacturer in the follower position, establishing a Stackelberg game between the two parties. In scenario dn, cooperation between the brand manufacturer and ordinary influencer forms a Nash non-cooperative game, in which both parties make decisions independently with the objective of maximizing their own profits. Subsequently, we compared the equilibrium results under scenarios ds and dn, focusing on exploring the conditions under which the manufacturer should choose the top-tier (ordinary) influencer for live-streaming sales.Second, we considered the centralized scenario denoted as scenarios cs (cn), which represent live-streaming sales by the top-tier (ordinary) influencer. Specifically, the brand manufacturer and top-tier (ordinary) influencer engage in complete collaboration and make decisions as a unified entity, with the objective of maximizing the overall profit of the dual-channel supply chain. By comparing the equilibrium results under centralized scenarios with those under decentralized scenarios, we found that the double marginalization effect reduces the supply chain’s operational efficiency. Therefore, we propose a “cost-sharing and two-part tariff” joint contract to coordinate the supply chain, and discuss the conditions under which this contract effectively coordinates the supply chain. In addition, we analyzed key parameters, including the proportion of free-riding consumers, the basic demand for live-streaming e-commerce, and the impact of the top-tier influencer’s personal influence on the scope of contract coordination.Third, is an extension in which we relax the assumption of homogeneous free-riding effects in the benchmark model. Specifically, we considered heterogeneous free-riding effects and numerically demonstrated that the core conclusions of the benchmark model remained robust.The important findings of this study are as follows. First, top-tier influencer live streaming sales may not always be advantageous for brand manufacturers. Specifically, when the top-tier influencer has significant personal influence, the brand manufacturer should choose the top-tier influencer. However, when the personal influence of the top-tier influencer is relatively low, the brand manufacturer should choose the top-tier influencer when the basic demand for live-streaming e-commerce is relatively low and the ordinary online influencer when the basic demand for live-streaming e-commerce is relatively high. Second, as the proportion of free-riding consumers increases, brand manufacturers are more inclined to choose top-tier influencers. Finally, under certain conditions, the “cost-sharing and two-part tariff” joint contract can effectively coordinate the supply chain.