The pulp and paper industry is an important contributor to global greenhouse gas (GHG) emissions1,2. Country-specific strategies are essential for the industry to achieve net-zero emissions by 2050, given its vast heterogeneities across countries3,4. In this paper, we develop a comprehensive bottom-up assessment of net GHG emissions of the domestic paper-related sectors for 30 major countries from 1961 to 2019—about 3.2% of global anthropogenic GHG emissions from the same period5—and explore mitigation strategies through 2,160 scenarios covering key factors. Our results show significant differences across countries in terms of historical emissions evolution trends and structure. All countries can achieve net-zero emissions for their pulp and paper industry by 2050, with a single measure for most developed countries and multiple measures for most developing countries. Except for energy efficiency improvement and energy system decarbonization, tropical developing countries with abundant forest resources should prioritize sustainable forest management, while other developing countries should pay more attention to enhancing methane capture rate and reducing recycling. These insights are crucial for developing net-zero strategies tailored to each country and achieving net-zero emissions by 2050 for the pulp and paper industry.