This study aimed to determine the relationship between supervisor training completed by first-line police officers and the level of job satisfaction reported by the police officers they supervise. This non-experimental, quantitative, comparative study used leadership theory to establish research questions. A comprehensive literature review developed considerations for training for police supervisors as well as the impact of job satisfaction in law enforcement. The population for this study included patrol officers and first-line supervisors at the Henderson Police Department in Nevada. Using the JDI/JIG survey and multivariate statistical analysis including ANOVA, the study concluded that job satisfaction, particularly general job satisfaction, was significantly impacted by supervisors’ hours of leadership training, level of education, and age.