The impact of energy conservation and emission reduction (ECER) policies on domestic waste control has not been determined. Previous papers have focused predominantly on industrial pollution rather than domestic waste control. To fill this gap, this paper evaluates the impact of the ECER demonstration city policy on domestic waste control based on Chinese city-level data from 2010 to 2020 using a staggered difference-in-differences model. This paper finds that the implementation of the policy has significantly increased the amount of urban domestic waste removed and the capacity for harmless disposal. A comprehensive examination of possible mechanisms reveals that ECER demonstration cities have achieved improved domestic waste control through channels such as increased government inputs in waste control, the promotion of green lifestyles among residents, and the promotion of technological advances in waste control. Detailed heterogeneity analyses reveal that the positive impact of the policy on domestic waste control is greater in cities at a high level in the administrative hierarchy, in eastern cities, and in large cities. This study has strong practical significance, as it provides insights supporting differentiated efforts to promote the construction of ECER demonstration cities and guidance for improving domestic waste control capacity by exploiting ECER policies.