Over the course of the last decade, food security in sub-Saharan Africa has risen to the top of the international development agenda. Concerns of food insecurity in sub-Saharan African have heightened in the context of rapid urbanization. Since the 1990s, supermarkets have been expanding rapidly throughout Southern and Eastern Africa. More recently, supermarkets have spread to Western Africa, including Ghana. This rise in supermarkets, often referred to as the “supermarket revolution”, is contributing to food supply systems changes in sub-Saharan Africa and is beginning to transform how urban consumers obtain sustenance. Although the expansion of supermarkets has been well documented, and many agree that this represents an important player in the urban food supply system, what the future food retail landscape will look like and how this will affect urban food security is not fully understood. This leads many scholars to question the ways in which the modernization of the food retail landscape may affect urban food security. This thesis reviews the current state of knowledge about the growth of supermarkets and its impact on urban food security. The aim of this paper is to contribute to the literature exploring how the growth of supermarkets is shaping food systems and in turn urban food security in Western Africa. More specifically, the objectives of this research are: (1) to provide a description of food retail shopping behavior and determine what factors contribute to food retail outlet choice; (2) to evaluate how supermarkets have affected access to food and analyze potential differences according to various socioeconomic groups; and (3) to analyze the dietary changes associated to patronizing supermarkets. This thesis presents and analyses the significance of findings from data collected in 2015 in Accra, Ghana. Insights gathered through household surveys (126), focus groups (3) and expert interviews (2) illustrate that, although traditional food retailers remain the major source of food, more people, particularly wealthier, more educated households living within close proximity of supermarkets, are purchasing more of their food from supermarkets. Findings from this study reveal that this may have caused modest changes in food security but that any possible changes are linked to wealth. These changes are reflected in the increased convenience, and improved access to greater quality foods, and preferred foods offered by supermarkets. In addition, households have experienced increased access to, and consumption of, processed foods mainly due to the cheaper prices, convenience and locations offered by supermarkets. This may be particularly relevant for lower-income households living within close proximity to supermarkets. These dietary changes have the potential to lead to serious diet-related health concerns such as the dual burden of undernutrition and overnutrition and obesity. Thus, further research is needed to fully understand the impact of supermarkets on urban diets.