Two basic activated carbons (Na+ and Cs+-Norit) have been used as catalysts in the synthesis of N-propargyl imidazole. The effect of the microwave irradiation has been studied. Under the experimental conditions used higher yields and selectivities of N-propargyl imidazole than those obtained using other basic media were reached. The carbons were characterized by thermal analysis, nitrogen adsorption and X-ray photoelectron spectroscopy. Most of the basic sites in the promoted carbons have 13.3 less than or equal to pK(a) less than or equal to 16.5. The order or basicity is Na+-Norit < Cs+-Norit. The basicity enhancement is directly connected with the size of the alkaline cation. The yield of the N=propargyl imidazole presents a maximum for 0.04 g of Cs+-Norit at 300 W in only 3 min of microwave irradiation.