A positive photoresist composition containing the combination of at least one alkali-soluble novolak resin and at least one light-sensitive compound represented by formula (I): ##STR1## wherein each of R.sub.1 to R.sub.10, which may be the same or different, represents hydrogen, --OH, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted alkylester group, a substituted or unsubstituted arylester group, a substituted or unsubstituted aralkylester group, a substituted or unsubstituted alkylsulfonylester group, a substituted or unsubstituted arylsulfonylester group, ##STR2## provided that at least one of R.sub.1 to R.sub.10 represents ##STR3## where R.sub.17 represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group or a substituted or unsubstituted aralkyl group; and at least two of R.sub.1 to R.sub.10 represent ##STR4## and R.sub.11 and R.sub.12, which may be the same or different, each represents hydrogen, --OH, --COOH, --CN, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aralkyl group, --COOR.sub.13, --R.sub.14 --COOH, or --R.sub.15 --COOR.sub.16 ; where R.sub.13 and R.sub.16, which may be the same or different, each represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl group; and R.sub.14 and R.sub.15 each represents a substituted or unsubstituted alkylene group, or a substituted or unsubstituted arylene group; provided that at least one of R.sub.11 and R.sub.12 represents a group other than hydrogen.The positive photoresist composition has high resolving power and sensitivity, and a nearly perpendicular cross-section.