For the restrictions that the fixed camera cannot automatically track the moving target, a rotatable camera system was designed based on the steering engine, in order to position and track the moving face. The Adaboost algorithm was used to detect and track the face. The face detectionpositioning– tracking system was designed under the development environment of Visual studio 2010 with the computer vision class library OpenCV and the graphical interface development framework Qt. The test results show that the accuracy rate for tracing face is 100% in the bright environment, and 95% in the dim environment. And it is also effective to tract the partially occluded face. This system can also be applied for security and other fields.