Background: The ability to self-regulate develops dynamically during the first five years and plays a crucial role in many areas of life. Emotional and behavioral self-regulation is a fundamental part of one’s social-emotional development, school readiness, successful school integration and the development of learning skills. The results from the impact evaluation of intervention programs support the case for early-childhood development and the point that developmental disadvantages can be compensated. All of these justify the need to adapt children’s self-regulation questionnaire as an instrument for Hungarian usage with sufficient reliability and validity. The screening of self-regulation difficulties in preschool and during the transition period between kindergarten and elementary school is of particular importance for the design of appropriate intervention programs and for the prevention of school disadvantages. Aim: The main aim of the study was to develop a Hungarian adaptation of the Child Self-Regulation and Behavior Questionnaire (CSBQ) and to test its validity through factor analyses on a sample of 3–6-year-old children with neurotypical development (n = 724). Methods: Following the standard steps of translation, the factor structure of the questionnaire was assessed using exploratory and hierarchical factor analyses. Our analyses resulted in a 19-item questionnaire, the criterion validity of which was tested using the Strengths and Difficulties Questionnaire (SDQ). Results: Based on the analyses of the Hungarian sample, a 19-item, bifactorial, three-dimensional Hungarian version of the Child Self-Regulation and Behavior Questionnaire was developed, which has good psychometric properties (fit indicators:. χ2(133) = 398.71, p < 0.001, CFI = 0.948, TLI = 0.933, RMSEA = 0.074, RMSEA CI90 = 0.065–0.082), Conclusions: The Hungarian version of the Child Self-regulation and Behavior Questionnaire is a valid measurement tool and can be used with good internal reliability to study the development of self-regulation, to screen for self-regulation difficulties in preschool and during the transition period from kindergarten to elementary school, as well as aid in the field of school readiness.