The study of fracture of thin aluminum rings due to shock loading generated by magnetic-pulse method was performed. This method provides experimental results on dynamic fracture under conditions of pure tension for a wide range of loading conditions. To simulate rapture of the ring samples a structural-temporal fracture criterion was applied. This criterion allows for analysis of the effects which are characteristic for the dynamic experiments. The fracture incubation time value and ultimate stresses are calculated for the aluminum rings subjected to pulse loading. An analytical relationship between the critical stress and the fracture time are obtained and this relation is in good agreement with the experimental data.