Phase-change materials (PCMs) are the subject of considerable interest because they have been recognized as potential active layers for onvolatile memory devices, known as phase-change random access memories. Ge-Sb-Te (GST) samples were prepared by pulsed laser (PL) and their basic physical and optical performances were studied. A Q- Switching Nd: YAG laser beam (λ=532 nm, repetition rate 6 Hz and the pulse duration 10 ns) has been used. The composition of GST was investigated by X-ray fluorescence and the analysis of the sample's surface was investigated by optical microscopy. The structure properties of (GST) were investigated by means of X-ray diffraction (XRD) to know the crystanility and amorphism of this material. The surface morphology of the samples has been studied by using Atomic Force Microscope (AFM), Scanning Electron Microscope (SEM). IR measurements show obviously the difference between the samples before and after using laser. The size of the nanoparticles observed at the center of the surface seems to be different from that at the edge of the surface.The order-disorder transition in GST is primarily due to a flip of Ge atoms from an octahedral position into a tetrahedral position without a rupture of the strong covalent bonds.