A condensed indan derivative represented by the formula (1) ##STR1## wherein the ring A is an optionally substituted benzene ring or a benzene ring which has lower alkylenedioxy group(s), the ring B is an optionally substituted benzene ring or a benzene ring which has lower alkylene dioxy group(s), and R is a group --NR.sub.1 R.sub.2, an optionally substituted nitrogen-containing heterocyclic group, a group --OR.sub.3 or a group --SR.sub.4 (wherein R.sub.1 and R.sub.2 are the same or different and each represent a hydrogen atom, a phenyl group, an optionally substituted nitrogen-containing heterocyclic group, or a lower alkyl group which may be substituted by optionally substituted amino group(s), lower alkoxy group(s), phenyl group(s), nitrogen-containing heterocyclic group(s) or hydroxyl group(s), and R.sub.3 and R.sub.4 each represent a lower alkyl group which may be substituted by substituted amino group(s)), provided that at least one of the rings A and B is a substituted benzene ring and R is not --NHCH.sub.3, and salts thereof, and medical use of said derivative and salts.