In order to optimize the ride comfort of the sliding door under the condition of meeting the handiness requirement，a respond surface method-based multi-object optimization method of the sliding door′s dynamic characteristics was proposed. The rigid-flexible coupled multi-body dynamic model of a MPV′s sliding door was established to investigate its ride comfort and handiness，and the results were verified by experiment based on a test rig. The motion mechanisms of the sliding door system were parametrically modeled and combined with the Latin hypercube sampling method. The sensitivity analysis was performed to study the effects of structural parameters on the sliding door's dynamics characteristics. Second-order response surface models of the dynamic indexes were established，in which correlation coefficients R2 are above 0.9. Finally，a multi-objective dynamic optimization on the sliding door was conducted by using NSGA-II algorithm. After optimization，the peak values of the middle guide roller load and acceleration of the door center mass were reduced by 39% and 24.4% respectively，and the time required for full opening was below 1.8 second. The ride comfort of the sliding door was improved significantly，while the requirement of handiness was met.