This paper reports the development of a new particle model to simulate fabric mechan ical behavior. A particle model of square meshes, which is close to the orthotropic structure of a woven fabric, is used to represent the fabric. In addition to the separation, bending, and shearing springs, a twist spring is introduced into the particle model to simulate the tension/compression, bending, shearing, and twisting behavior of the fabric. The forces and torques acting on the springs are derived according to fundamental elasticity mechanical laws. Experiments of the heart-loop test involving various fabric behaviors are conducted to validate the model. Comparisons between heart loops gener ated by the model and corresponding actual experimental results verify that the model is able to simulate fabric mechanical behavior with satisfactory accuracy. The anisotropy of woven fabric is shown by different heart loops formed by specimens in different direc tions, and is illustrated by the distributions of various inner stresses