We report the effects surface treatment and annealing had on the properties of InN layers grown using metal organic chemical vapor deposition (MOCVD). The number of defects due to N vacancies decreased significantly with increasing annealing temperature. However, when the annealing temperature reached 700°C, the crystalline grain became larger on the film surfaces. Annealing at an appropriate temperature improved the crystalline quality and the electrical properties of the InN films. However, when the annealing temperature was too high, InN oxidized and even dissociated.