Disclosed is a polycyclic ester containing a cyano group and a lactone skeleton, represented by following Formula (1): ##STR00001## wherein R.sup.a represents, for example, a hydrogen atom or an alkyl group having one to six carbon atoms which may have a halogen atom; R.sup.1s each represent, for example, a halogen atom or an alkyl or haloalkyl group having one to six carbon atoms; "m" is the number of R.sup.1s; "n" is the number of cyano groups; and CH.sub.2.dbd.C(R.sup.a)COO-- group may have either of an endo conformation and an exo conformation. Accordingly, there is provided a novel polycyclic ester containing a cyano group and a lactone skeleton which is useful typically as a monomeric component for highly functional polymers. A polymer, for example, derived from this compound is highly soluble in an organic solvent while remaining stable typically to chemicals and exhibits improved hydrolyzability and/or improved solubility in water after hydrolysis.