In recent years, concerns over youth unemployment have broadened to those about youth not in Education, Employment, or Training (NEET). The appeal of the "NEET" concept comes from its alleged ability to address a wide range of vulnerabilities amongst youth, including concerns about unemployment, early school leaving, and labour market discouragement. These concerns require attention as youths face the effects of economic crisis, especially in industrial economies, and global crises like the recent COVID-19 pandemic.Based on the PRISMA criteria, this scoping review identifies and maps the evidence on the risk factors of NEET youth. We included articles published between 2000 and June 2022, which resulted in 91 included papers. We categorised all the risk factors into eight major groups: individual characteristics, education and school, work, health, addiction, social factors, family, and environment.Overall, the findings indicate that education and family-related variables have a crucial influence on NEET youths. The most critical indicators were education level, work experience and skill, physical and mental health, marital status, poverty and social inequalities, living situation, parents' income, education, and job status. In addition, the review identifies various knowledge gaps concerning pertinent risk factors. More research to address these gaps and evaluate each risk factor's influence on NEET youth is advised.