Positive inotropically active 4-quinolyl-dihydropyridines of the formula ##STR1## in which R.sup.1 and R.sup.5 are identical or different and represent straight-chain or branched alkyl having up to 8 carbon atoms,R.sup.2 represents nitro or cyano, orR.sup.1 and R.sup.2 together form a lactone ring of the formula ##STR2## R.sup.3 represents a radical of the formula ##STR3## in which R.sup.6 -denotes hydrogen, halogen or straight-chain or branched alkyl or alkoxy in each case having up to 8 carbon atoms,R.sup.7 denotes aryl, thienyl or pyridyl, andR.sup.4 represents hydrogen, or optionally substituted alkyl, alkenyl, alkadienyl or alkynyl,and their physiologically acceptable salts.