Morphology control in bulk heterojunction (BHJ) solar cell is considered to be critical for the power conversion efficiency (PCE). In this paper, we present a novel approach that introduces polystyrene that organizes the poly(3-heacylthiophene) (P3HT) into columnar phases decorated by [6,6]-phenyl C-61-butyric acid methyl ester (PCBM) at the interface. This structure represents a realization of an idealized morphology of an organic solar cell, in which both exiciton dissociation and the carrier transport are optimized, leading to increased power conversion efficiency.