Objective: To improve quality of water extract of Angelicae Sinensis Radix and reduce production cost by investigating feasibility of purification and concentration process of water extract using ultrafiltration and nanofiltration integrated technology. Method: With retention rate of ferulic acid as index

ceramic membrane pore size

working pressure

filtration temperature as factors

orthogonal test was adopted to optimize ultrafiltration process of water extract of Angelicae Sinensis Radix.With leak rate of ferulic acid as index

interception relative molecular weight and solution temperature as factors

concentration process of ultrafiltrate was optimized by comprehensive test. Result: Optimum ultrafiltration process parameters were as follows:membrane pore size of 50 nm

filtration pressure at 0.10 MPa

filtration temperature at 50℃;retention rate of ferulic acid was more than 90%.Optimum nanofiltration process parameters were as follows:interception relative molecular weight of 200 Da

filtration temperature at 45℃;leak rate of ferulic acid was 0.1%. Conclusion: Ultrafiltration and nanofiltration integrated technology has many advantages

such as retention rate of active ingredients is high and material liquid is heated in a short time

it can improve quality of water extract of Angelicae Sinensis Radix with low production cost.