The reactive kinetics model for the preparation of inositol from the hydrolysis of sodium phytate was established through the theoretical analysis. Based on the experimental data, the hydrolysis kinetics of sodium phytate was studied by the 3-D surface fitting. The reaction was a first-order irreversible reaction, and its activation energy was 8.5×104 J/mol. The reactor used in the experiment was calculated by means of this hydrolysis kinetics equation, and the calculating data were compared with that from the actual reactor. The results showed that the relative error between the calculating reaction time and the actual reaction time is only 0.86%. The hydrolysis kinetics equation obtained could be applied to the practical production.