A transmission electron microscopy (TEM) study of heat-treated directionally solidified (DS) nickel-based superalloy, Rene 80, was conducted to understand the nature of boron rich second phase particle present along its grain boundary regions. The composition of the DS Rene 80 material was (wt%) 0.2C, 14.2Cr, 9.52Co, 4.0W, 3.98Mo. 0.02Nb, 0.18Fe, 2.9Al, 4.98Ti, 0.02Zr, 0.013B balance nickel. The alloy was subjected to standard solution heat treatment for 2 h at 1200°C, followed by ageing at 1025°C for 16 h. Thin foils from the aged material for TEM study was produced by mechanical polishing and dimpling to a thickness of less than 10 μm followed by ion milling. The presence of boride particles in heat-treated DS Rene 80 superalloy was observed to be effective in improving the creep performance and microstructural response of the material during high temperature exposure or processing.