This study examines the relationship between vertical wage disparity (hereinafter wage disparity, WD) within firms and future stock price crash risk (hereinafter CR) to identify the causes contributing to WD in Korean companies. Specifically, it analyzes how this relationship varies according to the level of founder family involvement in management and generational succession. Using data from non-financial firms listed on the KOSPI from 2002 to 2022, the study finds no systematic relationship between WD and CR. However, a significant positive relationship between WD and CR is observed as family involvement in management increases. Notably, among family firms, this positive relationship is only present in firms managed by subsequent generations. These findings suggest that expanding WD in family firms may result from insufficient internal monitoring and control mechanisms, and these negative effects may be more pronounced in family firms managed by subsequent generations.