The invention provides a multi-dimensional liquid
chromatography separation system. The
system comprises a high-performance liquid
chromatography gradient pump A, a high-efficiency liquid
chromatography gradient pump B, a high-performance liquid chromatography diluting pump, a gradient mixer A, a gradient mixer B, a sample injection valve, an enrichment column array A, an enrichment column array B, a
fraction collector, a liquid chromatography
separation column array, a
detector, a two-position eight-way valve and a connecting pipeline; and conversion between a previous one-dimensional separation state and a next one-dimensional separation state is realized through switching of the two-position eight-way valve, and
chromatographic separation of three dimensions or above is realized. A
chromatographic separation column of each dimension is selected through the liquid chromatography
separation column array; and on the basis of the same
gradient elution system and the same
detector, fullonline
monitoring and control of multi-dimensional chromatography separation are realized, and the cleaning degree of enrichment columns and separation columns is controllable. The separation of all dimensions is connected through the enrichment columns, and the diluting pump is used for assisting in enrichment or
trapping of compounds. Different chromatography
stationary phase and mobile phase combinations are selected, so that efficient separation of monomeric compounds in a
complex system sample with high separation difficulty is realized.