A process for producing a crosslink-cyclized cyclopentadiene, comprising the steps of reacting a cyclopentenone with an alkali metal hydride to thereby reduce the cyclopentenone (reduction step A) into a cyclopentenol; and reacting the cyclopentenol with a dehydrating agent to thereby dehydrate the cyclopentenol (dehydration step B) into a crosslink-cyclized cyclopentadiene of the general formula (III):
   wherein each of R 1 and R 2 independently represents a hydrogen atom or a linear or branched saturated alkyl group having 1 to 6 carbon atoms, n is an integer of 3 to 10, and the broken line in the 5-membered ring denotes that the 5-membered ring has two double bonds.