A smart city is a sustainable city that solves urban problems and improves citizens’ quality of life through the fourth industrial revolution technology and governance between stakeholders. With the advent of the fourth industrial revolution and the concept of smart cities changing, many smart city studies have been conducted. Still, studies on the overall flow of smart city research and major issues are insufficient. Therefore, this study analyzed the trends and characteristics of smart city research and proposes research directions through smart city literature analyses conducted over the past 10 years, from 2011 to 2020. This study conducted a systematic review of studies related to smart cities over the past 10 years. Smart city research was analyzed by dividing it into research methods and contents. In terms of research method, year, research methodology 1, research methodology 2, research purpose, data collection method, and use of research results were included in the analysis frame. In terms of research content, keywords related to research topics, analysis units, and the general classification criteria and security of smart cities were included. The research results mentioned in this study are expected to serve as useful guidelines for future smart city development projects.