Introduction: Fibromyalgia (FMS) is a chronic pain syndrome characterized by non-restorative sleep, and fatigue. Over 75% of individuals with FMS complain of poor sleep quality and fatigue. These have been ranked by patients with FMS as having great impact on quality of life. A literature review suggested that poor sleep quality may be a predictor of increased stress and FMS symptom onset in those affected. However, no experimental studies have demonstrated a causal relationship between poor sleep and stress in people with FMS. Methods: Using a single stage cross-sectional design, the primary study aim was to compare 25 women with FMS and 25 women without FMS, on the following variables: autonomic nervous system activity; perceived stress; sleep quality; immune function (cytokines); and fatigue. The secondary aim was to explore the relationships among the above variables within each group. A third aim was to assess the validity of the Autonomic Symptoms Profile by comparing it to measures of heart rate variability and selected sleep indices. Significant Results: The FMS group had worse sleep quality, more autonomic symptoms, and greater fatigue than the non-FMS group; they also had higher TNF-α levels. The non-FMS group was more likely to have OSA. Non-FMS participants who had OSA also had higher IL-1β values than the FMS group. Study variables that correlated with each other in the FMS group differed from those seen in the non-FMS group, with the exception of the positive correlation of total arousals with AHI in both groups. In the FMS group, fatigue was positively correlated with perceived stress, autonomic symptoms, and TNF-α; stress was positively correlated with autonomic symptoms; and AHI was negatively correlated with IL-1β levels as well as the above noted correlation with total arousals. In the non-FMS group, sleep quality was positively correlated with fatigue, and sleep quality and fatigue were positively correlated with IL-1β. IL-1β also positively correlated with TNF-α. Total arousals were negatively correlated with mean RR interval. SDNN was correlated with RR interval and negatively correlated with AHI. The hypothesis tests related to construct validity of the ASP indicated no significant supportive correlations.