Microstructure evolutions of nano-quasicrystals precipitated in ZrCuPt metallic glass ribbons during annealing has been examined by in-situ small-angle scattering and wide angle diffraction (SWAXS). The time-resolved measurements were made at a photon energy close to the Zr K absorption edge to obtain reasonable balance between transmission and resolution. During annealing the sample in vacuum, increase in SAXS intensity and diffraction peak at medium angle region was observed. The size obtained from SAXS and diffraction almost agreed, suggesting that the precipitation process in the glass ribbon is described by a growth process of single-crystalline nano-quasicrystals. Development of precipitated microstructure was further discussed by comparing SAXS profiles and diffraction profiles.