BACKGROUND AND OBJECTIVES: Transcranial Direct Current Stimulation is a neuromodulation method to treat neuropsychiatric and other diseases. This study aimed at evaluating the effect of this technique on pain and quality of life of fibromyalgia patients, in addition to studying brain images by Brain Perfusion Scintigraphy before and after procedures. METHODS: Prospective, double-blind, randomized, controlled study with parallel arms evaluated clinically and by CT scan with single photon emission (Brain Spect). Sample was made up of 20 female fibromyalgia patients divided in two groups of 10. Parameters evaluated were quality of life by the pain Visual Analog Scale, Quality of Life Questionnaire SF-36, Fibromyalgia Impact Questionnaire and pain level measurement on tender points with Fischer's Algiometer. The effective group has received 1.0mA anodal stimulation for 20 minutes in M1 to the left, cathode positioned on the right supraorbital region once a week in a total of 10 consecutive weeks. The Sham group received no electric impulses. RESULTS: There has been decrease in the Fibromyalgia Impact Questionnaire (55.36 to 35.42; p=0.0059) and the Visual Analog Scale (6.05 to 3.60; p=0.0316) scores. There has been statistically significant difference (p<0.05) in trigger points measurement in the effective group. For the effective group, the-Transcranial direct current stimulation in fibromyalgia: effects on pain and quality of life evaluated clinically and by brain perfusion scintigraphy* Estimulação elétrica transcraniana por corrente contínua em fibromialgia: efeitos sobre a dor e a qualidade de vida, avaliados clinicamente e por cintilografia de perfusão cerebral