Hydrometric observation was conducted at the headwater catchment in order to reveal the effects of the differences of forests management and tree species on hydrological response. Both small headwater catchments had similar hydrological conditions, such as, catchment areas, underlying geology, topography and soil depth. However, there were prominent differences in hydrological response between the unmanaged coniferous catchment (1.29ha) and the natural deciduous catchment (1.28ha). Hydrological response of the coniferous catchment was characterized by sharp discharge peaks and significant amount of quick flow. The amount of peaks and quick flow was approximately 1.5～3.0 times higher compare with the natural deciduous catchment. Hydrograph separation by EC indicated that the sharp discharge peaks were mainly composed of 'new water' (94.0～43.1%) during the typhoon storm at the coniferous catchment. On the other hand, the contributions of 'new water' to hydrological response were very small at the natural deciduous catchment. The total amount of overland flow at the unmanaged cypress forests was 4.2 times higher than that of the deciduous forests. In addition to overland flow, significant amount of biomat flow (shallow lateral flow through the organic soil horizons) occurred at the cypress forests during storms. In conclusion, overland flow and shallow lateral flow could significantly contribute to the hydrological response, especially to discharge peaks at the unmanaged coniferous catchment.