In various industries, the susceptibility of T91 steel to corrosion often necessitates the adoption of highly efficient surface coatings. Despite significant interest in developing a stable, cost-effective, and efficient graphene coating for T91 steel, achieving this goal has been challenging. To address this, electrodeposition was employed to apply Ni-reduced graphene doped with Ni/GO/TiO2 and GO/Fe-TiO2 nanocomposite coatings onto T91 steel substrates. Notably, the graphene nanocomposite coatings formed strong bonds with the T91 steel surface via Cr-C bonding, ensuring exceptional durability. Gravimetric, potentiodynamic polarization (PP), and cyclic voltammetry (CYV) experiments were conducted to evaluate the coatings' electrochemical response in a 3.5% NaCl solution. The Ni/GO/Fe-TiO2 coating exhibited a corrosion rate (CR) of 0.854 mm/y on T91 steel at room temperature, markedly lower than the untreated T91 steel CR of 2.321 mm/y. The method outlined in this study for producing graphene doped nanocomposite coated on the T91 steel is straightforward. The properties of deposition-coated surfaces were determined using XRD, SEM, and EDX analysis. Optimization studies are crucial in coating systems, with ANOVA being a commonly employed statistical technique. RSM was utilized to optimize the corrosion rate of T91 steel, measured using the weight loss method. Additionally, response optimization for CR identified a maximum fit of 74.39% after 24 h, with a weight loss of 0.00513 for Ni/GO/Fe-TiO2. The predicted R² (97.55%) and adjusted R² (99.25%) values are closely aligned, indicating the model's accuracy.