Tension and compression tests in three principle directions of the Kevlar fibril model have been conducted to determine the anisotropic elastic and strength properties of Kevlar. All-atom classical molecular dynamics method have been used to determine the Kevlar properties. Kevlar model is prepared from the known crystalline lattice. Reactive force field ReaxFF is used to model the atomic interactions. In ReaxFF, intra-chain bonded interaction will be modelled by covalent bond while inter-chain non-bonded interactions are modeled by hydrogen bonds, vdW and coulombic interactions. To check the topology defect effects, model with 5% defective chains are considered. Elastic properties obtained for the perfect model (i.e., model without any defective chain) are comparable with literature values. Presence of chain defects has effects on the strength properties of Kevlar.