To enable a data recording medium to discriminate by itself whether or not an electronic watermark is embedded in data.

When an electronic watermark detecting circuit 13 detects that data embedded with an electronic watermark in them are recorded in a memory 11, by turning on a switch 15 capable of controlling supply of power from a battery 17 to a notification device 16, any one or a plurality of items of notification information such as a sound, light, vibration and fragrance are outputted from the device 16. Further, the device 16 outputs notification information having different contents, depending on electronic watermarks having different contents which are outputted from the device 13. Still further, by using a data discrimination circuit 14 capable of discriminating data types of the data previously set by a user or classification information of the data types, the device 16 outputs notification information having different contents according to the classified data types or the classification information of the data types, corresponding to the contents of the electronic watermark detected by the circuit 13.