Since 2013, with the implementation of the toughest-ever clean air policy in China, the residential energy transition has been remarkable. However, how this policy affects household energy costs and its associated inequality remains unclear. In this paper, we assessed trends in the clean energy uptake in household stoves and fuels based on data from a large nationwide household survey and evaluated the energy cost inequality. We find that, during 2013-2017, about two-fifth (39.3%) of households using traditional solid fuel switch to clean energy, however, 60.9% of them are extremely poor or poor households. As this rapid transition campaign, although the national inequality in energy cost has been redressed significantly, the growing disparity in household income has caused a deep concern for the inequality in energy burden. The results suggest that, the average household spends about 5% (the median) of its income on energy, which is higher than the 3.5% the US households. Moreover, more than 45% of participants spent more than 6% of income on energy in 2017, while this number is about 25% in US. In addition, our findings suggest that there is a stark disparity of energy burden between urban and rural households. During 2013-2017, the energy burden on rural households is not reduced but increased due to the dramatic rise of cost on clean energy, while urban households tend to pay a lower and decreasing proportion of their income on energy. In this regard, the impacts of rapid energy transition differ widely in terms of urban-rural settings. Meanwhile, difference in this impact of energy transition on the household energy burden among climate zones is also recognized. Planning efforts on narrowing inequality among different income groups that more closely examine energy burden may accelerate household energy transitions that benefit the climate and human health.