A thermodynamic analysis on halide vapor-phase epitaxy of InN using InCl or InCl3 as In sources is described. The equilibrium partial pressures of gaseous species and the driving force for the deposition are calculated for growth temperature. It is shown that the deposition of InN is very difficult using InCl. On the contrary, by using InCl3, the deposition is possible under a condition of inert carrier gas or mixed carrier gas of hydrogen and inert gas. In the InCl3 system, hydrogen in the carrier gas plays a crucial role for the deposition of InN. These results agree well with the experimental data reported in the literature,