3D optical memory with photorefractive materials is discussed for ultra-high density/capacity memory exceeding the classical limit of a conventional optical recording system. Bit data are recorded as highly localized refractive index variations in 3D volume using a focused laser beam. We show recording and reading results using various recording materials and optical configurations. A multi-structured optical recording medium using a photoisomerization polymer and a transparent films has been developed for reflection confocal reading. Two-photon recording is also demonstrated.