The present invention provides a sulfonate of the formula (I'): ##STR00001## wherein Q.sup.1, Q.sup.2, Q.sup.3, Q.sup.4 and Q.sup.5 each independently represent hydrogen, alkyl having 1 to 16 carbon atoms, alkoxy having 1 to 16 carbon atoms, or electron attractive group, with the proviso that at least one of Q.sup.1, Q.sup.2, Q.sup.3, Q.sup.4 and Q.sup.5 represents alkyl having 3 to 16 carbon atoms or alkoxy having 3 to 16 carbon atoms, and at least one of Q.sup.1, Q.sup.2, Q.sup.3, Q.sup.4 and Q.sup.5 is electron attractive group; and A'.sup.+ represents a counter ion of the formula (IIa), (IIb), (IIc) or (IId) which are identified in the specification.The present invention also provides a chemical amplification type positive resist composition comprising a sulfonate of the formula (I) ##STR00002## wherein A.sup.+ represents counter ion, and Q.sup.1, Q.sup.2, Q.sup.3, Q.sup.4 and Q.sup.5 are as defined above; and resin which contains a structural unit having an acid labile group and which itself is insoluble or poorly soluble in an alkali aqueous solution but becomes soluble in an alkali aqueous solution by the action of an acid.