The feed point adjustable planar antenna includes a ground component, a main radiation plane, a branch line extended from the main radiation plane, and a ground pin electrically connecting the radiation component with the ground component. If it needs to fine tune the frequency band interval after the design of the antenna is completed, the feed position of the coaxial cable to the branch line can be changed to achieve the fine tuning without cutting the antenna. The ground pin extends from a side edge of the ground component and the branch line is adjacent to the ground component. The branch line and the ground component form a larger coupling range than the conventional planar antenna does. In the mean time, the coaxial cable also has a larger feed range than the conventional planar antenna does.