Abstarct: The reaction of 4,5-dihydro-3H-1,2,4-triazino[5,6-b]indole-3-thion and 3-(prop-2-one-1-ylthio)-5H-1,2,4-triazino[5,6-b]indole with propargyl bromide, afforded, 3-(prop-2-one-1-ylthio)-5H-1,2,4-triazino[5,6-b]indole and 5-(prop-2-one-1-yl)-3-(prop-2-one-1-ylthio)-5H-1,2,4-triazino[5,6-b]indole respectively. Then, the reaction of these compounds with different aromatic azides in the presence of catalytic amount Cu(OAc)_2 and sodium ascorbate at room temperature, new derivatives of 1,2,3-triazole lixnked 1,2,4-triazin[5,6-b]indole were prepared in good to high yields. The advantages of this reaction are high reaction yields, mild reaction conditions and short reaction times.