The reaction diffusion between indium solder and Au deposited (Ni and Cu) substrates was investigated. For the identification of intermetallic compounds, both Scanning Electron Microscopy (SEM) and X-Ray Diffractometry (XRD) were employed. Experimental results showed that the intermetallic compounds, such as Cu₁₁In₉ and In₂₇Ni₁₀, were observed for different substrates, respectively. Additionally, the growth rate of these intermetallic compounds was increased with the reaction temperature and time. We found that the growth of the intermetallic compound follows the parabolic law, which indicates that layer growth of the intermetallic compound was mainly controlled by volume diffusion over the temperature range. The apparent activation energies for intermetallic compound growth were 37.06 kJ/mol for Cu₁₁In₉ and 86.14 kJ/mol for In₂₇Ni₁₀, respectively.