In the present study, finite element analysis using ANSYS was carried to analyze the influence of particulate size, shape and position on Stress Intensity Factor (SIF) of thermoset composites. A representative study zone in front of crack tip was considered for the simulation in the Single Edge Notched Tension (SENT) specimen. Three types of reinforcement particulates were used namely circular, rectangular and capsule shaped. The volume fractions of the particulates were maintained as 0.03, 0.125, 0.282, 0.502 and 0.785%. Single reinforcement particulate was placed in and around the plastic zone formed ahead of crack tip. The shape and size of the plastic zone for a sharp crack and SIF was drastically altered with the correlation to the change of shape, size and position of the reinforcing element. From the analysis it was found that when the particulate was placed in front of crack tip, an average of 3.4, 7.34, 11.9, 17.3 and 21.7% of decrease in SIF was observed for 0.03, 0.125, 0.282, 0.502 and 0.785% volume fraction respectively. This decrease in SIF prevents the crack from unstable propagation, hence increasing load bearing capability of thermoset composite which intern increases the toughness. However when particulate was placed above the crack tip, SIF was increased by 1.9, 3.9, 5.2,6.1 and 6.7% over neat epoxy corresponding to the above mentioned volume fractions respectively, hence indicating unstable crack growth in the same direction of crack orientation.