Abstract: In this paper, a lattice model is presented to simulate the cracking processes of heterogeneous brittle materials. It is assumed in the model that a continuum is represented at the meso-level by a connected lattice of elastic-brittle truss or beam elements. The heterogeneity of the materials is implemented through change of element parameters. Fracturing is simulated by performing a linear elastic analysis of the lattice under loading and removing an element from the lattice that exceeds a certain failure threshold. Once an element is removed, the analysis is repeated. With this model, uniaxial tension and the four-point-shear experiments of single-edge notched beam are simulated. It is shown that the simulated crack patterns appear quite realistic.