A magneto-optical recording medium and a method for recording and
reproduction thereon are provided in order to reproduce information
recorded by multi-valued recording at a high S/N ratio. Disclosed is a
magneto-optical recording medium including two magnetic layers capable of
four-valued recording based on four combined magnetization states.
Magnitudes of reproduction signals concerning the four magnetization
states, obtained upon reproduction at a wavelength .lamda..sub.1, are
different from those obtained upon reproduction at a wavelength
.lamda..sub.2. The two magnetic layers, on which a signal (a) is
recorded, are irradiated with light beams having the wavelengths
.lamda..sub.1 and .lamda..sub.2 respectively. Signals (d), (e) reproduced
from respective reflected light beams are sliced by using at least one
slice level to obtain two-valued or higher multi-valued reproduction
signals respectively. The two-valued or higher multi-valued reproduction
signals (f), (g) from the respective wavelengths are mutually subjected
to logical operation to reproduce recorded information (i).