Currently, natural dye-based Dye Sensitized Solar Cells (DSSCs) have drawn enormous attention due to their numerous advantages, such as cost-effective, simple production system, and eco-friendly. The aim of this project was to conduct combined experimental and computational investigations on Cinnamon (Cinnamomum verum) extracts (Cinnamic acid and the cyanoacetic acid derivative of Cinnamaldehyde) used as natural dye photosensitizer for the application of TiO2 based DSSCs. The optical properties and the functional groups of the two dyes were determined by using UV-Vis and FTIR spectrometer, respectively. The band gap of the two dye molecules were estimated by using density functional theory (DFT) as implemented in Gaussian 09 software with a basis set of B3LYP/6-31G (d, p) level of theory. TiO2-based DSSCs were fabricated, containing I-/I3- as redox mediator and Graphite-carbon based FTO-glass as a counter electrode. The J-V characterization was done using Keithley Type 2400A Graphical Potentiostat. Compared with Cinnamic acid, the cyanoacetic acid derivative product of Cinnamaldehyde has shown red-shift on UV-Vis, and proved in FTIR. The HOMO-LUMO energy band gap was optimized from 4.93 to 3.73 eV, where the band gap of pristine TiO2 is 3.2 eV. The cyanoacetic acid derivative of Cinnamaldehyde based solar cell device offered the highest VOC, JSC, fill factor (%FF) and conversion efficiency (%Î·) characteristics of 0.4749 V, 0.1874 mA/cm2, 0.61088 and 0.054%, respectively. The derivatization process enhanced the conversion efficiency of the solar cell by 28.8%. In conclusion, this study showed notable improvement with the derivatization process on DSSCs performances.