Disclosed is an adjustment apparatus for adjusting an optical pickup capable of recording and/or reproducing plural optical discs of different sorts. The adjustment apparatus is an optical disc for adjustment (1) having a first signal recording layer (5) having a physical format in common with a CD and a second signal recording layer (7) having a physical format in common with a DVD. On the first and second signal recording layers, there are concentrically recorded EFM modulated data. The respective signal recording layers are provided with recording areas (8), (9) not overlapped with each other.