This paper integrates manufacturers’carbon emission reduction and retailers’low-carbon advertising into the analysis framework and introduces reciprocity into the strategies interactions of the low-carbon supply chain. By constructing and solving game-theoretic models, this paper tries to carry out the optimization decision-making and coordination mechanisms research. The results show that: 1) Regardless of the manufacturer’s reciprocal preference, the low-carbon supply chain can be perfectly coordinated through a combined contract of co-op advertising and carbon emission reduction cost-sharing. When the manufacturer has a highly altruistic preference, the low-carbon supply chain can be perfectly coordinated through the co-op advertising contract. When the manufacturer does not have a highly altruistic preference, the co-op advertising contract can only mitigate the double marginal effectsbut cannot achieve perfect coordination. 2) Under the two-way cooperation mode, the low-carbon supply chain generates the most carbon emissions while obtaining the highest profit. Both the overall profit and total carbon emissions are independent of the reciprocity coefficient. Under the advertising cooperation mode, both the overall profit of the supply chain and the total amount of carbon emissions increase as the reciprocity coefficient increases. Without any cooperation, the overall profit of the supply chain increases with the reciprocity coefficient, while the total carbon emissions decrease with the reciprocity coefficient. The reciprocal preference of the manufacturer is not only conducive to economic goals but also conducive to environmental goals. 3) No matter which cooperation mode is adopted, the total carbon emissions will first increase and then decrease with consumers’ low-carbon preference and advertising influence coefficient. When consumers’ low-carbon preference or advertising influence coefficient is small, the carbon emissions under the two-way cooperation mode are the highest.As consumers’ low-carbon preference or advertising influence coefficient increases, total carbon emissions under the two-way cooperation mode will first reach apeak and then decline sharply.