In this work, a surface plasmons resonance-based biosensor is theoretically and mathematically investigated. The proposed sensor is a multilayered structure of the titanium disilicide and graphene along with Ag metal. These layers are stacked over the BK7 prism. The metal, titanium disilicide, and graphene layer thickness are taken as 45 nm, 2 nm, and 1.7 nm, respectively. The titanium disilicide is an air-stable 2-D material. The performance of the biosensor is analyzed using the attenuated total reflection (ATR) method. The proposed configuration has a maximum sensitivity of 183.4°/RIU, 47.45 % higher than the conventional sensor. The designed sensor has wide applications in chemical, medical, and biological analyte sensing.