A digital signal recording and reproducing method and apparatus using first, second, third, and fourth information as information to protect a copyright, the first and second information are added to the digital signal, the third information is inputted from the digital interface together with the digital signal, a value of the fourth information is decided from a combination of the first to third information, and the fourth information is recorded onto the recording medium. The first information is information to control a copy restriction of the digital signal, the second information is information to perform a control about whether the signal is protected against the illegal use or not, the third information is information to indicate whether the signal has been encrypted or not, and the fourth information is information to control the copy restriction of the digital signal recorded on the recording medium.