Substituted furoylacetic acids and esters, and pharmaceutically acceptable salts thereof of the following general structure are useful as hypolipidemic agents: ##STR1## wherein Y represents oxygen or divalent sulfur; R represents a straight or branched alkyl chain containing from 10 to 20 carbon atoms and may be saturated or may be unsaturated containing from 1 to 4 double bonds; R.sup.1 represents hydrogen, or an ester group.