Abstract: BeO nanoparticles were synthesized by polyacrylamide gel route. The effects of the processing parameters on the morphology and size of the synthesized BeO nanoparticles were investigated. The calcination temperature of the gel precursor containing beryllium sulfate was determined by thermogravimetry and differential scanning calorimetry (TG-DSC), which is around 690 °C and 160 °C lower than the general temperature. X-ray diffractometry(XRD), transmission electron microscopy(TEM), and specific surface area measurements(BET) showed that the synthesized nanoparticles under 700 °C were pure, globular and about ~ 5-20 nm with narrow distribution. Interestingly, the nanograins coalesced and grew under higher calcination temperatures and longer calcination times. The influence of calcination temperature on the morphology and growth behavior is greater than that of its duration. The activation energy for grain growth was estimated to be 24.53 kJ/mol, and the dominant growth mechanism was most likely to be related to the vapor transport in pore control mode and grain-rotation-induced grain coalescence (GRIGC) mechanism.