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Abstract. Rape pod cracking is the main reason for mechanical harvesting loss. Seeds falling on the ground can easily become wild rape plants in the next season, and disturb the growth of normally sown. In order to choose the rape varieties with strong pod shatter resistance, a two- freedom collision tester which has two motion mechanisms of crank-rocker was designed. The operation method is to place 12 steel balls of 13mm diameter and 20 intact pods in the material box of the tester. Pods and steel balls were collided violently and equably under the motion of the two mechanisms and the shatter resistance index (SRI) is calculated to evaluate the pod cracking resistance. Contrast tests with pod three point bending fracturing method were also carried out, a total of three varieties were measured. In additional, the influence of pod moisture content and size on the SRI and cracking resistance force (CRF)were investigated. Results show that the method of two- freedom collision is stable and reliable, and the SRI declined with the decrease of the pod moisture content. However, there was little difference in cracking resistance of high moisture content pods. Besides, the SIR and CRF of rapeseed pod increased with the larger pod size. This study provides a reliable reference for the selection of rape varieties that suitable for mechanical harvesting.