The present invention aims to provide an optical data storage device capable of not only recording digital information by using holography, but also recording or reproducing information onto or from conventional optical discs represented by BD. In the optical data storage device of the present invention, a single light source is used for generation of both an optical beam for holographic medium curing and an optical beam for recording or reproducing information onto or from a BD or an HD DVD. Furthermore, the optical beam for holographic medium curing and the optical beam for recording or reproduction of information onto or from a BD or an HD DVD are designed to go through optical paths partly including a common optical path. In this configuration, multiple optical system configurations can be reasonably placed together into a single case.