Polybutadiene rubber (PBR) is the most elastic rubber formed from butadiene polymer. PBR finds wide application in the production of sportswear, golf balls, automobile components, shoe heels. PBR low glass transition temperature allows it to have excellent abrasion resistance (leading to longer tread life), excellent flexibility, and low rolling resistance. In order to improve wet traction, tread compositions often include natural rubber or styrene-butadiene rubber. This study aims to examine the effect of nano titanium dioxide (TiO2) on the mechanical, thermal properties of polybutadiene rubber (PBR) which was used as a filler. The amount of the TiO2 in the composite was varied to determine the corresponding effects on the thermal and mechanical properties of the polybutadiene rubber composite. The PBR/TiO2 nanocomposite was prepared using solvent mixing followed by two roll milling. By applying this technique, the homogeneity of the compound was significantly improved. This can be seen from the morphology observed by the scanning electron microscope (SEM). It was found that the increment of mechanical properties of the PBR/TiO2 composites with increased contents of nano-size TiO2. At 2 pphr, the TiO2/PBR nanocomposites exhibited better tensile test, hardness, and compression properties where it reaches 7.7 MPa, 47.1, and 9.33 MPa, respectively. Also, the thermal conductivity of PBR was improved with the addition of TiO2.