The invention provides an automatic tracking and focusing method and system for an integrated camera. A target object area is arranged, the proportion of the FV of the target object area is made to be larger than the proportion of the FV of a non-target object area, a focusing lens is driven to move, then, final searching judgment is performed, and finally, focusing is completed. The problem that the focusing position and actual expectation are not consistent when imaging is performed through the camera in a traditional 'hill climbing method' is solved, the focusing speed is high, and consumed time is short. After focusing, the target object area is tracked, and therefore the movement or position of a target object can be estimated, the focusing direction and the focusing area can be affirmed, focusing is triggered again when the target object area becomes vague or the displacement of the target object exceeds a determined threshold value, and it is guaranteed that automatic focusing is accurate. A step length changing searching method is adopted, efficiency can be improved, and automatic focusing speed is increased. A self-adaption estimation algorithm of an FV threshold value of a peak value area is adopted, and therefore automatic focusing can be faster.