This paper seeks to develop and validate the parental behavior scale by applying the theory of social constructivism. The study explores the main components of this parental behavior scale and verifies the validity of the scale. The relationship between the developed scale and related variables are also analyzed. A preliminary survey was conducted with 1,021 children and 78 classroom teachers in the Republic of Korea. To validate the developed scale, the main survey collected data from 1,674 children and 102 classroom teachers. The findings, based on a 24-item parental behavior scale, indicate the following four factors: instructional teaching (five items), mutual respect and cooperation (seven items), reflection orientation (six items), and autonomy encouragement (six items). A reliability analysis of the parental behavior scale indicated all four components were above the baseline value of 0.8, ensuring stable reliability and validity. This study takes a new approach to parenting research by applying the theory of social constructivism to the development of a parental behavior scale from the perspective of the mutual development of parents and children. This study contributes to filling the gap in knowledge style of child rearing based on social constructivism for the mutual development of parents and children in the field.