The invention mainly relates to an automobile performance computer-aided primary estimating method, mainly comprising the calculation of automobile control stability and its concrete steps are as follows: firstly establishing a movement model, taking a set of relative reference frame fixed on the automobile, taking the intersection of the center-of-gravity plumb line and side inclined axis of the whole automobile as an origin, using a lengthways horizontal axis of the automobile as an X-axis, using a line vertical to the X-axis and passing through the origin as a Y-axis, and using a plumb axis through the origin as a Z-axis, assuming all the angles on the horizontal plane as well as the corresponding angular speeds and angular accelerations are positive, counter-clockwise; obtaining a Z-axis moment balance equation, a Y-axis force balance equation, a Y-axis moment balance equation, and a main pin-axis moment balance equation. The beneficial effects of the invention comprise effectively forecasting the performance of the automobile products, largely reducing the trial-manufacturing and testing time and expenses and improving the efficiency and quality of automobile design.