<p>China’s family planning policy has led to low birth rates and population aging. While the two-child policy alleviated demographic imbalance in the short term, it has also increased the risk of household energy poverty. Using data from the China Family Panel Studies (CFPS) from 2012 to 2020, this study examines the impact of the two-child policy on household energy poverty. The results indicate that the policy, while successfully increasing second-child birth rates, also significantly raises the likelihood of household energy poverty. Mechanism analysis indicates that the two-child policy intensifies household energy poverty by reducing female labor participation, increasing housing requirements, and expanding intergenerational childcare. Heterogeneity analysis shows that rural households, low-income families, and those with limited education or poor health are especially vulnerable. By providing empirical evidence on the energy-related consequences of fertility policy reform in developing countries, this study offers both theoretical insights and practical policy recommendations for mitigating household energy poverty.</p>