Abstract: In order to study the dynamic mechanical properties of sea ice at high strain rate, a device of split Hopkins pressure bar (SHPB) is used to conduct dynamic impact tests on 2 kinds of sea ice specimens and a three-wave method is used to process the test data. Thus, the stress-strain relationship and the energy dissipation law of the sea ice specimens are obtained and the energy consumption characteristics of sea ice breaking are summarized. The results of the test show that the dynamic compressive strength of the sea ice is 17.1−40.0 MPa within a range of strain rate of 53.2−229.6 s⁻¹. Under the same air pressure, the sea ice specimen with an aspect ratio of 1.0 is smaller in both the strain rate and the peak stress than the specimen with an aspect ratio of 0.5. Under the action of the compressive stress the sea ice specimens show finally the characteristics of plastic pressure shear failure. When the strain rate is small, the sea ice remains as a whole after its destruction due to the viscosity of the ice. With the increasing of strain rate, the specimens are fractured and broken into pieces of blocks with different sizes. The strain rates of the specimens with the two aspect ratios influence greatly on the energy absorption rate ω of the sea ice dynamic destruction. However, the relationship curve between the energy absorption rate ω and the strain rate shows a different trend.