Abstract: To study the fracture morphology, hydraulic fracturing experiments were conducted by means of hydraulic fracturing device and specimen made of similar materials under condition of different stress. The results show that the probability of forming single fracture is greater than that of forming complex fracture morphology under two-dimensional stress conditions. The complexity of fracture morphology is closely related to experimental stress. When the values of triaxial stress （maximum horizontal principal stress, vertical stress, minimum horizontal principal stress） differ greatly, it is easier to form single fracture. While two parameters of them are close and both are different greatly in values, the fracture morphology becomes complex. There is an angle between main fracture and bifurcate fracture and the angle varies in different specimens, the fractures all propagate along the direction of parallel to maximum horizontal stress. Under the same condition, fracture morphology upon different fractured specimens are different from each other, which is related to the homogeneity of the specimen, flow path of fracturing fluid and feature of fractured surface.