This model of HPLC gradient system is equipped with 2 sets of high-pressure constant-current pump and ultraviolet detector. Its microprocessor reciprocating plunger pump comes with functions such as high working pressure, low pulse rate. This gradient HPLC model meet the needs of conventional analysis to micro flow analysis. This HPLC system has applications in the field of biochemistry, chemistry, pharmacology for chemical analysis, poison analysis and in protein food detection, medicine testing and polymer, environmental analysis.