Police officers have a higher incidence of disease and mortality rates when compared to the general population. Few studies have examined the link between lifestyle factors, occupational stressors and physiological dysfunction and how these factors lead to disease progression among police officers. The purpose of this dissertation was to examine the impact of physical fitness, lifestyle and occupational factors, perceived stressors, and sleep quality on various aspects of police officer physical, physiological and psychological health. Specifically, police officers (n = 116) completed several testing methods, both in the lab and field-based settings, assessing physical, physiological and psychological health. The first aim was to understand the influence of lifestyle and occupational factors on cardiovascular fitness and autonomic nervous system function among police officers. Not surprisingly, results indicated that officers who engage in regular exercise and have a low body fat also have higher aerobic fitness. There was not a significant relationship between heart rate variability indices and other lifestyle or occupational factors. The secondary aim was to examine the effect of perceived work stress on physiological biomarker expression for cardiovascular health. Results indicated that high scores on the Police Occupational Stress Survey (POSS) were related to higher pro-inflammatory cytokines (C-reactive protein (CRP) and tumor necrosis factor alpha (TNFα)). Finally, the purpose of the third aim was to examine the effect of sleep quality and shift-work on physiological biomarker expression in association with cardiovascular health. Contrary to what was hypothesized, day-time officers had higher levels of cortisol and total cholesterol expression than middle- or night-shift officers. In conclusion, poor lifestyle choices, unmanaged stressors, and constantly rotating shift schedules may contribute to increased allostatic load which can contribute to early, all-cause mortality among police officers. Future studies are needed that further examine cardiovascular health, sources of perceived stress, and sleep disturbances. Additionally, future research should examine the efficacy of interventions that address psychosocial factors and cardiovascular fitness among police officers.