The poly(styrene-b-2-vinylpyridine) diblock copolymer [poly(2-vinylpyridine) (P2VP), 22 mol%] was prepared by sequential anionic addition polymerization. This specimen showed thermal equilibrium morphology of dispersed P2VP spherical microdomains in a polystyrene (PS) matrix. After the introduction of Cu2+ (oxidant) into the P2VP spherical domains, oxidation polymerization was performed by exposing the ionic complex films as a template to a mixture of pyrrole and water vapour. The films obtained were dissolved in organic solvents such as benzene, tetrahydrofuran and chloroform. These oxidation products exhibited the structure of polypyrrole core/PS shell type microspheres with narrow particle size distribution.