An AD(Advertisement) system is provided to enable a user to use charged contents free or at a discounted price, offer an AD effect to an advertiser by inserting AD data into the charged contents, return a part of AD expense provided to user-defined AD from the advertiser to social service, and increase social service participation of the user by displaying the user-defined AD. An AD editing module(710) provides an editing interface for editing the charged contents to an area borrowed as an ASP(Active Server Page) area among the webpage areas provided to a member and combines the AD data to the charged contents selected by the member. An AD expense processing module(720) processes a charge of the charged contents including the AD data with the AD expense of the advertiser providing the AD data. The AD expense processing module calculates the AD expense for the AD based on counts requesting AD insertion to a service server. A donation managing module(730) accumulates a part of the charge of the charged contents as the donation and processes the remaining as the AD expense. The donation managing module inserts a donation mark into the charged contents.
