Novel indolo[3,2-b]quinolines (1b-k), having a nitro, amino, acetamido, methanesulfonamido, or glycosylamino group at the 2, 7, or 8-position, were prepared and their antitumor activities against P388 leukemia in mice were examined. The 7-galactopyranosylamino derivative (1g) showed the most potent activity (optimal dose = 25 mg/kg, T/C > 333%, cure rate 5/6).