Numerous studies have focused on age as one of the most robust correlates of prison misconduct, with younger inmates more likely to commit disciplinary infractions compared to their older counterparts. However, less empirical attention has been paid to the conditioning effects of additional demographic variables such as sex or race/ethnicity on the age-misconduct relationship. The current study, thus, further extends prior research on age and prison misconduct by examining potential interaction effects between age and sex (i.e., male and female), and separately, between age and race/ethnicity (i.e., non-Hispanic white, non-Hispanic black, and Hispanic). Negative binominal regression models are used to examine 137,552 inmates admitted to state prison in Florida from 1995-2000. Analyses indicate that overall, there are no substantial differences between males and females or between racial/ethnic categories when examining the relationship between age and prison misconduct. However, the youngest offenders warrant some attention for their visible differences in levels of misconduct for both males and females and for Hispanic, black, and white inmates. Research and policy implications are discussed regarding the potential variation in the age-misconduct curve, especially for younger inmates.