Ti-Al intermetallic compound porous material was prepared by the element mixture partial diffusion-reactive synthesis-sintering method. Its tensile deformation was studied experimentally. The effect of porosity on the tensile properties and its microscopic fracture mechanism in tension were revealed. Results show that the tensile stress-strain curve can be divided into four stages: elasticity, yielding, strengthening and failure without necking. Its mechanical properties (including elastic modulus, yield strength and ultimate strength) decrease with the increasing of the porosity and the elongation is much lower than 5%, indicating obvious brittleness at room temperature. The characteristic of the fracture surface is of brittle fracture in macroscopy and of transgranular and intergranular fracture existing simultaneously in microscopy, which is closely related to the microstructure of the dense Ti-Al intermetallic compound.