This paper empirically quantifies environmentally augmented rural household incomes in Cambodia and analyzes how economic land concessions (ELCs) affect such incomes. Data is derived from a structured survey of 600 randomly selected households in 15 villages in three study sites in Cambodia, where local livelihoods are highly reliant on access to land and natural resources, supported by qualitative data from focus group discussions. Gini coefficient decomposition, multiple regression models, and propensity score matching (PSM) models were employed to analyze the composition of income portfolios, determinants of major income sources, and the impacts of land grabbing on incomes. Results documented high reliance on environmental income (32–35% of total household income) and farm income (51–53%) across income quartiles; demonstrated the variation in product composition across quartiles and the contribution of each major product to income inequality; and identified the main household characteristics influencing absolute and relative incomes. ELCs were found to consistently have negative impacts on household total income, environmental income, size of available cultivable land and livestock holdings, and increasing the distance to forests. The total household annual income subjects to ELCs were estimated to decrease by 15–19%. While providing some employment opportunities, we find no evidence of positive income effects of ELCs on households in the areas where ELCs are located.