Abstract: The manufacturing precision of slot in the plane slotted-array antenna has a great effect on the electrical performance. In order to avoid the shortcomings of assumptions and approximations made by some traditional methods during the course of studying the effect, a new method using support vector regression is proposed to obtain the prediction model of electrical performance affected by manufacturing precision, according to the data from the manufacturing of plane slotted-array antennas. Moreover, a method minimizing both model fitting capabilities and generalization as the objective function is offered to choose the proper parameters of support vector regression and facilitate the application. Simulation research shows that the proposed method can accurately predict the effect and has better generalization compared with BP neural network and least squares regression.