A data read/write device includes a data write-processing unit that performs amplitude modulation on write data to obtain an amplitude-modulated signal that contains a plurality of amplitude levels, correlates a plurality of data included in the write data with each amplitude level of the amplitude-modulated signal to obtain amplitude data, and transmits the amplitude data to a magnetic head that writes the amplitude data into a memory area of a recording medium, and a data read-processing unit that reads the amplitude data via the magnetic head from each memory area of the recording medium, and converts the amplitude data into readable read data.