In the present study, finite element simulation using ANSYS was conducted to analyze the influence of particulate shape, size and position on Stress Intensity Factor (SIF) of thermoset composites. For the purpose of simulation a representative study zone in front of crack tip was considered in Single Edge Notched Tension (SENT) specimen. Two types of reinforcement particulates were used namely rectangular and capsule shaped. The volume fractions of the particulates were maintained as 0.03, 0.125, 0.282, 0.502 and 0.785%. Apart from variation in size and shape, orientation of particulate was considered (horizontal and vertical). 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 4.3, 11.3, 18.6, 25.4 and 30.8% 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 2.2, 4.8, 6.7, 8.0 and 8.9% over neat epoxy corresponding to the above mentioned volume fractions respectively and which is an important information useful for design of structural elements.