Disclosed is a method for distributing and clearing digital contents via on-line which is performed by a system for distributing and clearing digital contents via on-line that includes Internet, systems of users who are consumers and distributors of digital contents through the Internet and a main system having a database for storing a list of the digital contents. The user system downloads and installs a dedicated program having a function of watermarking the digital contents and a function of executing the watermarked digital contents. The user system searches the systems of other users if the user system intends to purchase or download the digital contents, and the dedicated program performs watermarking of the digital contents when the digital contents are downloaded to the user system. A settled amount through a settlement system according to the purchase of the digital contents is distributed to a rightful owner of the digital contents and a user who has distributed the digital contents in the predetermined ratio.