Abstract: Taking pure metal as raw materials, bulk amorphous alloy (Zr56Co28Al16)98Y2 with different diameters (different cooling rates )was fabricated by magnetic floating melting and water-cooling copper mold techniques, and amorphous ribbon with same composition was fabricated by melt spinning method with high cooling rate. The effects of cooling rate on microstructure and mechanical properties were studied. The results indicate that with the decrease of cooling rate, plasticity of bulk amorphous alloy decreased, while its hardness increased, and the free volume in amorphous alloy decreased. In addition, there were nanocrystals embedded in the amorphous matrix. The plasticity, however, was not enhanced by the absence precipitation of nanocrystals. The more free-volume would result in a better plasticity of the amorphous alloy.