A structure of an electrostatic speaker and a manufacturing method thereof are provided. In the electrostatic speaker, an electrode and a vibrating film are disposed closely, and electrostatic force of the vibrating film may make the vibrating film contacting with the electrode such that the speaker would fail to generate the sound. Thus, the invention provides a spacer structure and a manufacturing method thereof. Various patterning or height changes and other designed are performed to place the spacer between the electrode and the vibrating film, so as to prevent the electrode from contacting with the vibrating film. The disposition of the spacer is expected to enhance frequency response or sound volume of the speaker.