The shock tensile stress-strain curves of 93% wt. tungsten alloy at different strain rates εand different temperatures T were measured experimentally by use of a Hopkinson tensile bars equipment. Based on these experimental data, two constitutive models were proposed to represent the shock tensile behavior of this alloy. Besides, a linear relation between the critical strain ε₁ of plastic instability and the plastic work W₁ at the maximum load-onset of instability was derived, so that the criterion of shock tensile fracture of the material is given in this paper. The fractal analysis to the tensile fracture was made which gives a strong support to the conclusions obtained from the macro-experimental results.