ABSTRACT The objective of this study was to develop a short and reliable Family Dynamic Environment Scale (FDES) that would better serve the needs of mental health professionals in detecting the potential for delinquent behavior in Korean adolescents related to a dysfunctional family dynamic environment. Semi-structured interviews with 30 adolescents were initially conducted to generate a set of items, after which, 44 participants were included in method test–retest reliability test. Finally, 544 participants recruited by proportional stratified random sampling were included in a factor analysis. The original version of the FDES had 60 items in 7 categories; the final version included 42 items grouped into 5 factors. Both test–retest reliability and Cronbach's α coefficient were high for the final version of the scale. As a result of factor analysis, five factors were extracted: family psychological climate, parent–child relationship, paternal parenting attitude, family cohesion, and maternal parenting attitude. These contributed 50.3% of the variance in the item scores. All 42 items loaded above .35 on their respective factors. The Cronbach's α coefficients for internal consistency were .95 for the total 42 items and .92, .81, .82, .78, and .71, respectively, for each of the 5 factors.