The thesis describes a method for human-computer interaction through vision-based gesture recognition and hand tracking, which consists of five phases: image grabbing, image segmentation, feature extraction, gesture recognition, and system mouse controlling. Unlike most of previous works, our method recognizes hand with just one camera and requires no color markers or mechanical gloves. The primary work of the thesis is improving the accuracy and speed of the gesture recognition. Further, the gesture commands will be used to replace the mouse interface on a standard personal computer to control application software in a more intuitive manner.