Abstract: This study aimed to optimize the extraction technology of dietary fiber from Oenanthe javanica using single-factor experiment and orthogonal array. Combined method of enzymolysis and alkaline hydrolysis were applied to optimize the extraction of dietary fiber, and the water holding capacity and swelling capacity of extracted dietary fiber were evaluated. The optimal enzymolysis conditions were determined as follows: enzyme-to-substrate ratio, 40 ∶ 1 U/g, enzymolysis temperature50 ℃, enzymolysis time 1.5 h. The optimal alkaline hydrolysis conditions were determined as follows: liquid-to-solid ratio30∶ 1 ( m L/g) , sodium carbonate concentration 2.5%, alkaline hydrolysis temperature 30 ℃, alkaline hydrolysis time 1 h.Under these conditions, the extraction rate of total dietary fiber ( TDF) , soluble dietary fiber ( SDF) , insoluble dietary fiber were47.94%, 4.78% and 43.16%, respectively.The content of dietary fiber in leaf of O.javanica was much higher than in stem, and SDF also possessed higher proportion in TDF from leaf.The water holding capacity and swelling capacity of TDF from O.javanica were 389%, 6.27 m L/g, respectively.TDF from leaf had higher water holding capacity and swelling capacity than those in stem, probably because of the higher proportion of SDF.