Increasing the adoption of energy-efficiency measures (EEM) by households is one of the practical strategies to increase energy efficiency and reduce greenhouse gas emissions. For the 3.24 million low-income households in Australia, partly due to their potentially disproportionately large waste of usable energy, there is a gap between the potential for energy efficiency through existing EEM and the actual energy-efficiency level. Many measures increase energy efficiency in buildings; however, barriers persist for such households to adopt these measures, of which limited research has yet to be conducted. In response, this study examines the relationships involved by a questionnaire survey of 212 low-income households in Australia, showing that financial barriers have the greatest influence, followed by split incentive barriers, with the provision of information having no significant role to play. This paper contributes to filling the gap of limited energy-efficiency research involving low-income households, revealing the effect of energy-efficiency barriers on their adoption of EEM.