The application of bi-injection molding, a simple variation of the conventional injection molding process, is limited because of the lack of a good control of the weld line location. The weld line is an inevitable consequence of the meeting of two polymer melt fronts from different gates in the mold cavity. Positioning the weld line to avoid critical areas for the sake of aesthetics or mechanical strength is the key to the success of bi-injection molding. This remains a challenge for control engineers. This paper proposes a two-time-dimensional model predictive control for the process by combining a conventional model predictive control with an iterative learning control to explore the repetitiveness of the process. To predict the final position of the weld line, the approach takes the geometric dimension of the mold cavity into consideration. Simulation shows that the proposed method has good ability to control the weld line position ultimately within a narrow range of the desired position.