Abstract: A liquid chromatography having an on-line cleaning function, comprising a first flow channel (L3), a second flow channel (L21), an analysis flow channel (L22) and waste liquid flow channels, further comprising a cleaning flow channel (L25), a direction switch valve (V1) and a multi-flow channel switch valve (V2), etc. The liquid chromatography changes the flow path of the liquid by changing the communication relationship between the two-position switch valves, thus realizes the on-line cleaning function for a first chromatographic column (C1), a middle chromatographic column (C2), a filter or a protector (B2) respectively, and realize the simultaneous on-line cleaning function for the first chromatographic column (C1) and the middle chromatographic column (C2).

Abstract: A liquid chromatography having an on-line cleaning function, comprising a first flow channel (L3), a second flow channel (L21), an analysis flow channel (L22) and waste liquid flow channels, further comprising a cleaning flow channel (L25), a direction switch valve (V1) and a multi-flow channel switch valve (V2), etc. The liquid chromatography changes the flow path of the liquid by changing the communication relationship between the two-position switch valves, thus realizes the on-line cleaning function for a first chromatographic column (C1), a middle chromatographic column (C2), a filter or a protector (B2) respectively, and realize the simultaneous on-line cleaning function for the first chromatographic column (C1) and the middle chromatographic column (C2).