The present work aims to modify conventional low density polyethylene (LDPE) by preparing its particulate composite with cenosphere. Cenosphere is a potential waste produced in bulk from the coal fired thermal power plant. In this context, surface modification of cenosphere was done by γ- aminopropyl triethoxy silane (ATS) coupling agent. Furthermore, LDPE was grafted by glycidyl methacrylate (GMA) to be used as compatibilizer. The resulting surface modified and unmodified cenosphere as well as glycidyl methacrylate grafted LDPE (LDPE-g-GMA) were functionally characterized by Fourier Transform Infrared (FT-IR) spectroscopy. LDPE-cenosphere particulate composites were processed in their different formulations and evaluated with various properties such as thermal stability, mechanical properties, chemical resistance and flow behaviour. Dispersibility of cenosphere in LDPE matrix was studied by Scanning Electron Microscopy (SEM). Series of analysis was performed in order to understand the effect of cenosphere content and its modification on the final properties of particulate composites. Mechanical properties were found to be statistically significant as per ANOVA and Post hoc Tukey HSD test. Particulate composites prepared with modified interphase were observed to possess good combination of properties.