Go-TiO₂ composites are gaining importance because of their applications in various fields and also due to their stability. In this work, we have reported for the first time, interaction of Graphene Oxide (GO) with TiO₂ nanocluster. To understand the interfacial interaction between GO and TiO₂, we have proposed GO-TiO₂ models through simulations. The calculated optical properties of theoretical models were compared with experimentally synthesized RGO-TiO₂ composite. Optical absorption spectra indicated enhancement in visible region for RGO-TiO₂ nanocomposite when compared to that of TiO₂. The variation in optical properties of RGO-TiO₂ cluster with degree of functionalization was also studied. It was observed that in GO-TiO₂ model with optimum OH groups, new states were formed within the band gap which could be responsible for enhanced absorption in visible region.