Purpose: The purpose of this study was to develop an instrument to measure the parenting behavior of primary caregivers of childrenin early childhood. Methods: An instrument was developed according to Devellis's instrument development process. The participantsin this study who completed the main survey were 370 mothers and grandmothers. The survey was conducted from June 1to July 30, 2014, and collected data were analyzed using item analysis, half-split reliability and Cronbach’s α coefficient, exploratoryand confirmatory factor analysis, convergent validity. Results: The factor structure of the instrument showed the cumulative varianceas 55.7% in the factor analysis. As a result of a confirmatory factor analysis, a four-factor structure was found to be appropriate,and the construct validity and convergent validity of the instrument were thereby confirmed. The finalized parenting behaviorinstrument consisted of 26 items and four independent factors: affectionate, laissez-faire, educational and impulsive. A five-pointLikert scale was employed, and a higher score in a particular factor showed that most of the behaviors belonged to the factor. Conclusion:The instrument developed in this study was found to be reliable and valid, and can be used to develop parent-child relationshipbuilding.