Abstract: In this work we studied the influence of the microwave irradiation in polar Diels-Alder reactions between nitropyrrole and nitroindole derivatives acting as electrophiles with dienes of different nucleophilicity. The cycloadditions was performed under two conditions using benzene as the reaction medium and solvent free. The results clearly confirm that the use of microwave irradiation in this type of reactions have advantages in relation to the carried out under classical heating, though in general the products obtained are similar, but with lower reaction times and increases in the yield.