The proper disposal of waste rubber without disturbing the environment is one of the most challenging tasks towards the researchers and scientists in the 21st century. The existing disposal techniques other than recycling of waste rubber goods, does not add any value either on the waste polymeric material or in the raw material from which those polymeric materials are originated. The mechanochemical devulcanization of waste natural rubber by bis(3-triethoxysilylpropyl)tetrasulfide and its subsequent dispersion in fresh natural rubber-silica composites in various proportions ranging from 20% to 70% wt% are both addressed in this investigation. The mechanical performance of the composites clearly indicates that tensile strength, tear strength and elongation at break gradually increases with increasing devulcanized rubber (r-NR) content up to a certain proportion and the values are much superior to that of the control formulation. The evaluated mechanical properties clearly specify that the optimum level of r-NR in the composite is 40 phr. The developed green composites showed superior thermal behavior compared to that of its control formulation. The rubber filler interaction between devulcanized natural rubber (r-NR) and silica was further explored by measuring the fraction of immobilized polymer chains using differential scanning calorimetry. Scanning electron microscopic images (SEM) of the r-NR based NR/r-NR/SiO₂ composites reveal a homogeneous and uniform dispersion of the silica filler.