Rollover crashes can be the most dangerous vehicular crashes among all crash types which have a higher fatality rate than other kinds of crashes. The orthogonal design was adopted to evaluate structure parameters how to affect the vehicle rollover crashworthiness in dolly and curb-trip tests. It is simulated with a finite element model of SUV, which has been developed previously. The parameters are based on maximum vertical roof deforming velocity, maximum vertical deformation and lateral roof deformation which nearby occupant head. They have been selected as dependent variables or responses which reflect roof stiffness and roof crush magnitude respectively. There are 11 structure factors which have an effect on the vehicle rollover crashworthiness. It can be determined under the location of crash zone in rollover. Those factors have significant effects to the vertical roof deformation, lateral roof deformation and vertical roof deforming velocity. The result can be obtained from a series of the analysis. The main effects are compared with those factors to vertical and lateral roof deformation in dolly and curb-trip tests.