Herein two conjugated donor molecules, TDPP-POCN and FDPP-POCN, with planar diketopyrrolopyrrole (DPP) as the core building-block acceptor unit and phenoxazine-capped acrylonitriles as arms are designed and synthesized. Solution-processed bulk-heterojunction organic solar cells based on blends of the small-molecule donors and [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) exhibit promising photovoltaic device performance with a maximum power conversion efficiency up to 4.8 % for TDPP-POCN and 3.4 % for FDPP-POCN under the illumination of AM1.5G, 100 mW cm–2. To the best of our knowledge, this is the highest efficiency reported so far in DPP–phenoxazine-based systems and among acrylonitrile-bridged donor-π-acceptor-π-donor-structured small-molecule donors for solution-processed small-molecule-based organic solar cells.