This article describes the preparation of macroporous cross-linked poly(dicyclopentadiene) by chemically induced phase separation. Dicyclopentadiene was polymerized and cross-linked by metathesis in the presence of 2-propanol, using a ruthenium-based catalyst, and then dried under vacuum. The resulting porous materials were characterized by SEM, density measurements, and mercury porosimetry. By varying the initial 2-propanol content, it was shown that closed or open cell porosity could be obtained, with narrow pore size distributions and micrometric average access diameters. A linear dependence of the pore volume fraction and the initial a-propanol content was also observed, suggesting easy tailoring of the former.