The solid-state amorphization of Al Pt multilayers and the crystallization of the solid-state amorphized Al-Pt alloy thin film are studied with in situ electrical resistance and X-ray diffraction measurements. The amorphous Al-Pt alloy is highly resistive and has a negative thermal coefficient of resistivity. The Avrami analysis of the crystallization of solid-state amorphized Al-Pt alloy in conjunction with X-ray diffraction data and transmission electron microscopy observation, shows that it transforms polymorphically to the cubic equilibrium phase Al2Pt. The results of kinetic measurements are discussed with respect to recent experiments and theories in solid-state amorphization.