This paper describes hydrolysis rate of aluminum nitride; AlN (s) + 3H₂O (l) → NH₃ (g) + Al³⁺ + 3OH^-, in which effect of temperature on the hydrolysis rate was mainly examined. In the experiments, powder of aluminum nitride, 1.0 g in mass and 1.2 μm in average diameter and 99.9 mass% in purity, was charged into 1.0 liter of sodium hydroxide solution with the concentration of 1.0 M at different temperatures 295 K to 327 K, and then the concentration of aluminum ion in the solution was periodically monitored by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). As a result, the hydrolysis rate of aluminum nitride increased strongly with increasing temperature. The hydrolysis rate was well described as second order reaction governed by concentration of aluminum nitride, C_AlN; -r_AlN= -dC_AlN/dt = kC_AlN², and k = 2.38×10⁶ exp(-64.6×10³/RT) (m³ mol^-1 s^-1). The result offers many benefits for understanding the mechanism of aluminum nitride hydrolysis, preventing corrosions of aluminum nitride, and controlling the generation of ammonia.