The Matra MS9 was a Formula One car used by the Matra International team during the 1968 Formula One season. It only raced once in a world championship race, driven by Jackie Stewart at the 1968 South African Grand Prix, before being replaced by the Matra MS10. At its only outing, it qualified third, but Stewart had to retire due to a connecting rod failure.

After success with their Formula 2 programme, Matra had plans to compete in Formula 1 with a car powered by their own Matra Sports V12 engine. However, Ken Tyrrell, who had run Matras in his own Formula 2 team, persuaded Matra to construct a car powered by the Cosworth DFV engine. To develop the concept, a Matra MS7 F2 car was modified to take a DFV, with suspension components taken from the Matra Group 6 sports car.

Despite its role as a development car, the MS9 was entered into the 1968 South African Grand Prix, as the MS10 was deemed to be not ready. Still in its pale green primer coat, Jackie Stewart was immediately comfortable with the car and eventually qualified third on the grid behind the Lotus 49s of Jim Clark and Graham Hill. The intense heat at Kyalami led to cooling problems, and the nose-cone off the car was widened to improve airflow. An additional radiator was also fitted at the rear of the car. In the race itself, Stewart beat the Lotuses at the start but was soon overtaken by Clark and then some time later by Hill. Just after half-distance a broken connecting-rod punched through the side of the engine and the new car's race, and its racing career, was over.

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