The invention discloses a radio frequency switch device based on the electrowetting driving principle and a preparation method thereof. The device comprises a lower polar plate, an upper polar plate and liquid drops placed between the lower polar plate and the upper polar plate. The lower polar plate comprises a first substrate, a driving electrode layer, a dielectric layer, a radio frequency electrode layer and a first hydrophobic layer, which are arranged in turn. The upper polar plate comprises a second substrate, a ground electrode and a second hydrophobic layer, which are arranged in turn. The liquid drops are placed between the first hydrophobic layer and the second hydrophobic layer. According to the radio frequency switch device disclosed by the invention, an aqueous solution is driven to move to different positions to control the on-off of a radio frequency circuit, so that the control is simple, the automation degree is high, and the application range of microfluidic, radio frequency switch and other techniques is greatly expanded.