A new multibranched crystalline Molecule was synthesized through Horner-Emmons reactions Using hexyl-substituted thiophene-based carbaldehydes as dendrons and benzene-1,2,4,5-tetramethylphosphonic acid octaethyl ester its the core unit. The molecule was employed to fabricate organic photovoltaic (OPV) cells with methanofullerene [6.6]-phenyl C61-butyric acid methyl ester (PCBM). Poly(3-hexylthiophene) (P3HT) wits also used its a dopant to improve the film quality and power conversion efficiency. As a result, the short-circuit current density and open Circuit voltage were increased when P3HT was added into 4(HPBT) and PCBM dyad. resulting in a hi,,her power conversion efficiency of around 0.6%.