The purpose of this research is to study the interrelation between Urbach energy (Eu), optical band gap energy (Eg), and complex dielectric constant (ε) in relation to the disorder induced properties of SiO2/rGO thin films. The rGO-like carbon was created by annealing coconut shell carbon (csc) at different temperatures of 400oC, 600 oC, and 800 oC. From the analyses, it obtained Eg which was varied from 2.01 eV until 2.67 eV. While Eu from 0.13 eV until 0.26 eV. The results showed that the Eu varied inversely to the Eg. The Penn model and hydrogen-like atom model theories were used to investigate the interrelation between Eu and ε. Finally, it is shown that the Urbach energy is linearly and inversely related to the imaginary and real parts of dielectic constant, respectively.