To explore the mechanism and law of shattering and damage of fresh grape cluster during the whole period of harvesting and transportation,the construction method of vibration and collision coupling dynamic model of grape cluster was investigated.The improved vibration and collision coupling model of rape cluster was proposed based on the original vibration model of grape cluster. According to the proposed model, the vibration dynamic equation of grape cluster was obtained to describe the rachis and fruits based on absolute node coordinate formulate and the branches and fruit stems based on natural coordinate formulation,respectively.The expression of elastic force and stress of rachis and fruits was proposed based on the principle of virtual work and continuum mechanics, and the expression of collision force was obtained based on Hertz model and Kelvin model.The derived expressions were substituted into the vibration dynamic equation of grape cluster to establish the vibration and collision coupling dynamic model of grape cluster, and the solution method was also briefly explained.