Computational thinking (CT) is considered a key competence in today’s digital era. It is an emerging construct that relates to critical thinking and creativity. Research on its assessment is in the process of consolidation. This systematic review aims to analyze studies that have used CT assessment instruments for children and adolescents aged 4 to 16 years in order to identify which variables, they assess and their psychometric properties. The search and analysis were carried out following the PRISMA statement protocol, analyzing 50 articles published between 2006 and March 2023. An increase in the publication of CT measurement instruments is observed, with 54% of them supported by evidence of validity and 88% by reliability, highlighting construct validity, followed by content and criteria validity. China leads in the number of publications, while Asia and Europe concentrate most of the research. There is a noticeable contribution from South America, evidencing the lack of participation from Central and South American countries in this field of study.