A radiation-sensitive composition containing a resist compound A, an acid generator B, and an acid crosslinking agent C. The resist compound A is (a) a polyphenol compound which is produced by the condensation of a C5-45 aromatic ketone or aromatic aldehyde with a C6-15 compound having from 1 to 3 phenolic hydroxyl groups, and, (b) its molecular weight is form 300 to 5000. The radiation-sensitive composition is solvent-soluble and exhibits a high sensitivity, high resolution, and high heat resistance.