A simplified model describing the complicated boiling water reactor (BWR) kinetics is developed by combining two different approaches: the analytical and the experimental, the latter based on the dynamic data system methodology. This model is capable of adequately representing the BWR main dynamics, which can be, in turn, conveniently used to predict its kinetics. Although the system exhibits some highly nonlinear characteristics, it is approximated by a linear model. By using Peach Bottom-2 real operating data without perturbation, the dynamics of the BWR are experimentally identified, and the results are found to be in close agreement with those obtained by the General Electric Company.