As a common support method for working face and advanced roadway, the hydraulic support often bears the impact load from the roof during the working process, and its own stability is threatened. Under the premise of ensuring the safety of hydraulic support, taking the self-moving unit support ZQ2000 / 22 / 48 A of advanced roadway as the research object, the dynamic response characteristics of unit support under gradient impact load are simulated by using SOLID WORKS model and dynamic software ADAMS, and the displacement and stress variation law of top beam and column are obtained. The maximum stress of single column is 1850 kN, the maximum subsidence is 100 mm, the maximum relative displacement of top beam is 5.84 mm, and with the impact load 200 kN in turn. With the increase of 600 kN and 1000 kN gradients, the parameters such as the subsidence, stress and offset of the column and the top beam show nonlinear changes, and the increment and change rate gradually increase, which provides a theoretical basis for the strength selection and impact test analysis of the hydraulic support.