Abstract: As a special means of river restoration in hydraulic engineering construction, culvert mainly functions as a water channel for road and bridge system, and for local aquatic animals to passing through barriers. Since the hydraulic design of culvert fishway is rarely reported in China, theoretical basis for the construction of culvert fishway is insufficient. By analyzing some experiment data of culvert fishway abroad, we summarized the hydraulic characteristics and flow fields of classical baffle systems of culvert fishways,including offset bafe(OB),slotted-weir bafe(SWB) and weir bafe(WB).We obtained the expressions of dimensionless flow rate, water depth, slope against velocity, and compared the working performance of the three baffles.The research achievements would provide theoretical basis and reference for the internal transformation and hydraulic design of culvert fishway in China.

Key words: culvert fishway, offset baffle, slotted-weir baffle, weir baffle, hydraulic characteristics, flow field distribution