Introduction: Fatigue is a common symptom in patients with cancer. Objective: Toexamine the prevalence and independent predictors of fatigue in women with breastcancer. Material and Method: A cross-sectional study with a nonrandom sample of163 patients in outpatient follow-up. Fatigue was assessed by the Piper Fatigue Scale.Results: Clinical relevant fatigue (score ≥ 4) was present in 31.9% of the sample andthe average intensity was 6 (SD = 1.3).Pain and depression were factors independentlyassociated with fatigue. Conclusions: The association of fatigue, pain and depressionconfirmed the existence of cluster of symptoms. The management of fatigue is poorlyunderstood, but depression and pain may be treated and may provide relief fromfatigue.