This invention discloses a method of protecting copyright of a digital video work by using a digital password technology and a digital watermark technology to prevent the unauthorized use of a digital video work. Such method adds password protection of two chrominance arrays of such video work in advance, so that when such video work is published on the Internet, it can only be played in color by a specified player. As long as a user enters the correct password into the specified player, a full color visual effect of such video work can be obtained. If other players are used to play such video work, only a partial gray-scale visual effect can be obtained. Users must request or buy a specific player and a password from the distributor of such video work to play the complete information to prevent piracy.