The performance of alloyed CdS0.33Se0.67 quantum dots-sensitized solar cells (QDSSCs) is studied. Fluorine doped Tin Oxide (FTO) substrates were coated with 20 nm-diameter TiO2 nanoparticles (NPs). Presynthesized CdS0.33Se0.67 quantum dots (QDs) (radius 3.1 nm) were deposited onto TiO2 nanoparticles (NPs) using direct adsorption (DA) method, by dipping for different times at ambient conditions. The FTO counter electrodes were coated with platinum, while the electrolyte containing I−/I− 3 redox species was sandwiched between the two electrodes. The characteristic parameters of the assembled QDSSCs were measured at different dipping times, under AM 1.5 sun illuminations. The maximum values of short circuit current density (Jsc) and conversion efficiency (η) are 1.115mA/cm2 and 0.25% respectively, corresponding 6 h dipping time. Furthermore, the Jsc increases linearly with increasing the intensities of the sun light which indicates the linear response of the assembled cells.