We examined the nucleation and growth behavior of a nano icosahedral phase from a supercooled liquid region in the Zr65Al7.5Ni10Cu7.5M10 (M=Ag or Pd) glassy alloys by differential scanning calorimetry and transmission electron microscopy. It is found that the growth rate of the icosahedral phase is nearly constant at the initial stage and much slower than that of the Zr2Ni phase in the Zr65Al7.5Ni10CU17.5 glassy alloy. The maximum homogeneous nucleation rate of the icosahedral phase in the Zr65Al7.5Ni10CU7.5Ag10 glass is calculated as 4.4x10(20) m(-3)s(-1) at 695 K, which is approximately 10(4) times higher than that of the Zr2Ni phase in the Zr65Al7.5Ni10CU17.5 glass. The nucleation rate of the primary phase increases significantly and the growth rate at the crystallization temperature decreases with increasing Pd content. Thus, the addition of Ag and Pd is effective for the increase of the number of nucleation sites and the suppression of grain growth, which is the main reason for the formation of icosahedral nano particles. It is, therefore strongly suggested that an icosahedral short-range order exists in the glassy stale of the present alloys.