ObjectiveMalnutrition in the Democratic Republic of the Congo (DRC) has declined over the past 2 decades. However, malnutrition inequality persists. Evaluating trends of socioeconomic disparities in malnutrition among children under 5 y of age in the DRC can help target meaningful interventions. MethodData from the Multiple Indicator Cluster Survey (2001, 2010, 2018) assessed the prevalence of underweight, stunting, and wasting among children under 5. The Slope Index of Inequality (SII) and the Relative Index of Inequality (RII) measured socioeconomic inequalities. We evaluated trends in the entire national sample and stratified subsamples based on place of residence and wealth index quintiles. The final sample included 42 976 children. ResultsThe national prevalence of underweight and wasting decreased from 31% to 26% and 13% to 6% in rural and urban areas. However, trends in stunting prevalence varied between the two areas. Nutritional disparity widened between low- and high-income families (stunting RIIs: 0.61 in 2001, 0.37 in 2018; stunting SIIs: –0.20 in 2001, –0.40 in 2018; underweight RIIs: 0.53 in 2001, 0.35 in 2018; underweight SIIs: –0.21 in 2001, –0.28 in 2018). Urban areas experienced greater inequality than rural areas (stunting in urban RIIs: 0.41 in 2001, 0.33 in 2010, 0.25 in 2018). ConclusionDespite progress in reducing malnutrition, persistent socioeconomic disparities, particularly in urban areas, remain a serious public health concern in the DRC. Addressing the root causes of malnutrition and ensuring socioeconomically equitable access to nutrition is critical to promote the full potential of children.