Abstract: The division of underground drinking water source protection areas in scientific and reasonable ways can prevent water sources from being polluted in the most precise ways and with a lower economic cost. The MODFLOW model was utilized to develop and calculate a simulation of the groundwater flow field of the Hutuo River groundwater source area in Shijiazhuang City. By utilizing the MODPATH, the 100 days and 1 000 days reverse migration trajectories of the tracer particles subjected to two different working conditions were calculated. The results were as follows: the average migration distances of the tracer particles at the end of 100 days under each of the two conditions were 0.54 km and 0.49 km; moreover, the average migration distance of each of the tracer particles at the end of 1 000 days was 6.1 km and 5.6 km. Also, the simulation considered the change of the groundwater flow field under the condition of utilizing the infiltration field. By analyzing the calculation results of these two working conditions, it was concluded that when the pumping wells inside of the water source area were generalized into the well groups, the specific trajectory geometry of the tracer particle reverse migration was more regular, and its migration distance was relatively short. At the same time, by considering the specific water supplement situation of the infiltration field, the whole infiltration field was included in the first-grade protection area as well.