In the current work, ZnO nanoflowers have been synthesized via sol-gel technique using a mixture of zinc-nitratetetrahydrate, ammonia and polyethylene glycol (PEG). Variation in PEG concentration and ammonia evaporation delay time was performed and the resulting nanoflowers have been investigated using x-ray diffraction (XRD) and scanning electronmicroscope (SEM). To explore the potential of the resulting ZnO nanorods, a prototype of dye sensitized solar cell (DSSC) has been fabricated. For this purpose, the nanorods were grown directly on conducting ITO substrates by nanoseeding technique. With a variation in nano seeding time for 2, 4 and 6 days, followed by hydrothermal process at 80°C for 20 hours, ZnO nanorods with average diameter of 82, 332 and 1385 nm have been synthesized. The performance test showed the resulting open circuit voltage (Voc) was increased from 398 to 486 mV when the diameter of ZnO nanorods increased from 82 to 332 nm. However, the Voc decreased slightly to 456 mV when the nanorods further increased to 1385nm. The phenomenon is related to the interaction between the semiconductor oxide and the Ruthenium complex organic dye.