Poly(N-vinylcarbazole)/polystyrene composites were prepared through simple radical polymerization of N-vinylcarbazole in the presence of polystyrene. Honeycomb-patterned composite thin films were fabricated by casting the composite solutions under humid conditions. The scanning electron microscopy (SEM) images of the resulting honeycomb pattern on the composites show a higher regular structure compared to those of films prepared from the poly(N-vinylcarbazole) homopolymer. The pressure-area isotherms and photoelectrochemical behaviors of the patterned films were also observed. The photoconductivity of the patterned thin films increased with increasing poly(N-vinylcarbazole) concentration. This enhancement is attributed to the effects of the honeycomb structures and the charge transfer across the donor/acceptor hybrid interface in the composite films.