In the decision on the pros and cons of the optical and electrical properties of organic solar cells, the morphology has proven to be very important. Easy to change the morphology via adding a small amount of additive, because proton dissociation constant is the main reason for their application. In this study, the use of poly(3-hexylthiophene) and [6,6]-phenyl C 61-butyric acid methyl ester as the donor and acceptor materials, and were subsequently doped with different quantity of 4,4′-sulfonyldiphenol, 4,4′-dihydroxybiphenyl, biphenyl-4,4′-dithiol. When the proton dissociation constant is higher and lower respectively, the morphology reveals earthworms-like and fiber-like. For the reason that when the additive is biphenyl-4,4′-dithiol, it can improve the power conversion efficiency of about 27% and the incident photon-to-current conversion efficiency of about 12%.