BACKGROUND: Harmful use of alcohol is a major cause of global morbidity and mortality. The role of alcohol as a driver of the unfolding non-communicable disease crisis has led to high-profile calls for better epidemiological data. Despite causing a disproportionate amount of harm in low-income groups, there is a critical dearth of evidence on the intra-national socioeconomic patterning of alcohol use in low- and lower-middle income countries (LLMICs). This review aims to fill the gap, providing evidence on the association between socioeconomic status (SES) and alcohol use in these low-income settings. METHODS: We conducted a comprehensive literature search for primary research published between January 1, 1990 and June 30, 2015 using 13 electronic databases, including Embase and Medline. We also hand-searched references and reviewed 'gray literature' - studies that have not been published in peer-reviewed journals. We included studies from LLMICs presenting data on multiple measures of socioeconomic status and alcohol use. No age or language restrictions were applied. Due to high heterogeneity, we used a narrative approach for data synthesis. FINDINGS: After reviewing 4242 records and 247 full-text articles, 23 studies met our inclusion criteria, reporting data on 861,295 individuals aged >10 years from 10 countries. Alcohol use was found to be more prevalent in lower socioeconomic groups in the majority of Southeast Asian studies. The association was mixed for African studies, although these tended to have smaller sample sizes and weaker methods. Studies that measured multiple domains of SES found good agreement between different indicators. Definitions of alcohol use and abuse varied widely between studies, as did socioeconomic groupings. CONCLUSIONS: The lack of consistency between studies and the abject lack of data from the majority of LLMICs present a major barrier to policymakers tasked with reducing alcohol-related harm in these settings. Adherence to standardized definitions, the publication of WHO survey data on alcohol and SES, and enhanced surveillance is needed to build an accurate picture of the socioeconomic patterning of alcohol use in developing countries.