Abstract Background: Overnutrition has emerged as a major problem in China. Measuring the associations of socio-economic variables with energy intake and its fat density is important, particularly at the upper tail ‘overnutrition’ areas of their distributions. The present study aimed to estimate such associations, with an emphasis on overnutrition areas. Methods: The study used data on individuals aged 20–45 years from the 2006 China Health and Nutrition Survey (n = 3407). Quantile regression methods were employed to determine associations with key drivers at various parts of the conditional distributions of energy intake and its fat density. Results: Household income was found to have little association with energy intake, and only a poor one with fat density of intake (a 1000 Yuan increase in household income was associated with a 0.1–0.3% point increase in fat density across the distribution). Although women had lower energy intakes than men, their energy intake was more fat dense at 1.5% points on average. Urban residents not only had lower energy intakes than rural residents (a 300 kJ difference at the lower tail, rising to a 600 kJ difference at the upper tail), but also more fat-dense intakes (a 2.7% point difference on average). Conclusions: The small income relationships estimated indicate that dietary excess may no longer only be a problem of the rich in China. A lower energy intake but higher fat density of intake associated with men compared to women and rural compared to urban residents indicates a need for flexible nutrition policy targeting.