3-Indolecarboxamide compounds of the formula: ##STR1## inclusive of pharmaceutically acceptable acid addition salt and/or hydrate forms thereof, wherein R.sup.1 is hydrogen or C.sub.1-4 alkyl; each of R.sup.2 and R.sup.3 is hydrogen, halogen, C.sub.1-4 alkyl, C.sub.1-4 alkoxy, benzyloxy, C.sub.2-6 alkanoyloxy or hydroxy; R.sup.4 is hydrogen or C.sub.1-4 alkyl; R.sup.5 is hydrogen, halogen, C.sub.1-4 alkyl, C.sub.1-4 alkoxy or hydroxy; R.sup.6 is hydrogen or C.sub.1-4 alkyl; X is oxygen, sulfur or direct bond; each of k and m is an integer of 1 to 3; and n is 1 or 2, are useful as drug for the prevention and treatment of various circulatory diseases.