A surface plasmon resonance (SPR) biosensor utilizing an indium phosphide (InP) semiconductor and graphene material layer and placed on an Ag metal-based biosensor is proposed to detect the sucrose concentration in water. The SPR biosensor works on the principle of attenuated total reflection. The transverse matrix method has been utilized for the reflectance calculation. The thickness of the Ag layer, InP, and graphene are taken as 45 nm, 2 nm, and 2 nm, respectively. When three layers of InP and a single layer of graphene are taken, and the maximum sensitivity of the sensor 506  deg  /  RIU is obtained. The desired values of performance parameters, such as full-width half maximum and quality factor were computed and obtained as 6.94 deg and 72.86  deg RIU^−  1 respectively, which recommend the significance of the proposed work. Graphene is used to enhance the bio-compatibility of the analyte with the sensing layer. The refractive index of the sensing medium is considered as 1.33. Indium phosphide is an air-stable optical material. SPR biosensors have wide applications in detecting and analyzing biomolecules and biochemicals.