The characteristics of hydrologic design parameters for small hydro power(SHP) sites located in four major river systems have been studied. The model, which can predict flow duration characteristic of stream, was developed to analyze the variation of inflow. And another model to predict hydrologic performance for SHP plants is established. The results from hydrologic performance analysis for SHP sites located on five major river systems based on the models developed in this study show that the specific design flowrate and specific output of SHP site have large difference between the river systems. The load factor, however, have small difference compared with specific design flowrate and specific output for all river systems. Also, it was found that the models developed in this study can be used to predict the primary design specifications of SSHP plants effectively.