Introduction: Thromboangiitis obliterans is an inflammatory and segmentary obstructive disease, which affects arteries and small and middle veins of the extremities. Aim: Evaluation of microcirculation, hemodynamics and reactivity of the microcirculation by Doppler laser flowmetry on patients with Buerger disease. Material and methods: We examined 32 patients with Buerger disease (Papa-Adar scoring positive criteria) admitted to the 2nd Medical Clinic Tîrgu Mureş. To evaluate the microcirculation we used a Doppler laser flow meter, assessing the values of the basic flow of the microcirculation in arms and legs and the reactive postocclusive reactive hyperemia, as well the reactivity at cold exposure. Results: Examination of the basic flow shows a flattening of p waves at acral level in arms and legs as well. The reactive postocclusive hyperemia presents increased values of time to peak flow and lower values of hyperemia (peak flow). (upper extremity 59,13±22,23%, lower extremity 49,93±20,15% p=0.08). The test of cold exposure was positive for 23 patients, with an average decrease of the basic flow at cold stimuli by 40,09±16,6% and in the subgroup with a positive test of 58,17±11,6%. Conclusions: Laser Doppler flowmetry examinations in patients with thromboangiitis obliterans shows morphological changes of acral microcirculation waves in arms as well in legs. The reduced peak flow and prolonged time to peak of the reactive postocclusive hyperemia confirms the pathological changes of the microcirculation, of the blood flow reserve and of the total vasodilatation capacity in the arms and legs as well. Laser Doppler flowmetry is an useful method in the evaluation of these microhemodynamic modifications.