Vulnerability is a concept that evolved out of the social sciences and was introduced as a response to the purely hazard-oriented perception of disaster risk in the 1970s. Recently, the study about social vulnerability of human system and coupled human-environmental system has become increasingly more popular in the field of vulnerability research and sustainability science. The concept of social vulnerability aims at identifying and understanding which groups of people may be more sensitive and susceptible to the impacts of natural disasters and why. In this article, we discuss the progress of social vulnerability research and review the concept, characteristics, analytical frameworks, and assessment methods of social vulnerability. This article first reviews definitions of social vulnerability from different types of stresses including risk and hazard, climate change, demographic characteristics and inequality, resource exploitation, land use change, and environmental pollution. Social vulnerability is one dimension of vulnerability. Social vulnerability refers to negative impacts of social system exposed to natural or human factors due to its own sensitivity characteristics and lack of ability to cope with adverse disturbance. Second, this article introduces several analytical frameworks of social vulnerability from political economy, social-ecological system, and comprehensive perspectives. These frameworks include the Pressure and Release Model, Sustainable Livelihood Framework, Hazards-of-Place Model, Coupled Human-Environmental System Framework, BBC Conceptual Framework, and MOVE Framework. Strictly speaking, these frameworks are not specialized social vulnerability framework, and most of them were derived from vulnerability frameworks. Some researchers improved and applied them to explain elements, process, and mechanism of social vulnerability. The article compares critical rationale of different frameworks and reviews their merits and defects from three perspectives. At last, the article summarizes assessment methods, computational formulas, and evaluation index systems of social vulnerability. The methods include comprehensive index, function model, back propagation artificial neural network, decision tree, object-oriented analysis, spatial multi criteria evaluation, and GIS methods. Every method has different features and advantages and disadvantages. The choice of method should be based on research purposes. There are also many kinds of evaluation index systems and social vulnerability indexes such as the SoVI, CVI, CCSVI, SV, and so on. Most studies use population and relevant social and economic indicators to establish evaluation index systems. However, there are many questions about the validity and reliability of index systems. Generally, current studies on social vulnerability have the following problems: a unified conceptual and analytical framework has not been formed; assessment methods of social vulnerability are too simplistic; a comprehensive evaluation index system is absent; studies on mitigation and countermeasures are insufficient. In the future, social vulnerability study needs to establish a unified concept and analytical framework, expand the research contents, improve theoretical system, and promote multi-disciplinary integration. At the same time, it is necessary to improve evaluation index system and method of social vulnerability, strengthen research on social vulnerability mitigation and countermeasures, and integrate social vulnerability and social adaptation. We hope social vulnerability research can provide the scientific basis for social adaptability and sustainable development.