An improved method of loop antenna and improved loop antenna thereof are provided, the method is used to generate an antenna resonant frequency for a conformed specific communication by modifying a resonant wavelength of a basic loop antenna. The improved method of loop antenna includes the following steps: connecting a first antenna radiator to a resonant point of the basic loop antenna electrically, and using an additional length from the connected first antenna radiator additional length to increase the resonant wavelength of the basic loop antenna, in order to generate an antenna resonant frequency conformed to the specific communication system.