A hydrological model is one of the tools developed by science to better understand and represent the behavior of the river basin. The IPH2 model aims to use it for projects in urban and rural basins. It is a model that uses few parameters and it is based on known methodologies. The objective of the research was to analyze the hydrological flow behavior in the Poxim Açu River sub-basin through modeling with the IPH2 model, as well as to model the flow of the Poxim River basin with a model that does not require a lot of input data and to calibrate the IPH2 model for the studied basin. After the automatic and manual calibration phases, parameters for hydrological simulation were found. After the simulation, the value found for NSE was 0.73 for the coefficient of determination (RSR) the value generated was 0.74, PBIAS found after calibration was-7.44, the value of the RMSE was 0.95, and the RSR value found was 0.07. According to the results of the present study, it was possible to conclude that the calibration process for the flow behavior of the Poxim-Açu River basin responds positively to what the literature considers satisfactory.