Fatigue is commonly reported by patients with rheumatoid arthritis (RA), and it is frequently used to evaluate disease activity and response to therapy. We theorized that the feeling of fatigue in patients with RA may be a manifestation of disturbance of sleep. Sixteen patients with chronic, active RA, who were selected for early onset of fatigue (<6 hours after morning awakening), were extensively evaluated by formal all‐night polysomnographic recording and multiple sleep latency testing (MSLT). Although no sleep deprivation was found, all patients had some type of marked disturbances of sleep, including unanticipated sleep apnea (2 patients), frequent movement of extremities (all 16 patients), and frequent arousal (all 16 patients). The alpha‐delta sleep pattern was present in 13 patients, and 7 were found by MSLT to be hypersomnolent. None of the patients accurately recognized the degree of their sleep disruption. Our findings from the MSLT indicate that fatigue in patients with RA may be a manifestation of sleep fragmentation, rather than a nonspecific constitutional symptom.