We have developed a Doppler broadening measurement Gamma-induced Positron Spectroscopy (GiPS) system, and performed a demonstration measurement for cm size Zr based amorphous and crystallized alloys using a laser Compton scattering (LCS) gamma-ray beam with a maximum energy of 16.9 MeV at the NewSUBARU synchrotron radiation facility, Hyogo, Japan. This method makes use of positrons generated inside the sample by implantation of highly energetic gamma-ray photons. GiPS can be a non-destructive measurement for bulk size material in air. In this study, the result of the Doppler broadening measurement is in good agreement with the density change caused by crystallization.