Abstract: The invention relates to a liquid chromatography based on a very small liquid feeding rate, where a liquid sample containing components to be detected, such as anion species, is mixed with an eluting solution, the resulting liquid mixture is continuously passed through a separation column, whereby the components to be detected are held in the separation column, then a predetermined amount of an extraction liquid as an aliquot is injected into the stream of the liquid mixture, and the liquid mixture is continuously passed through the separation column after the injected extraction liquid has passed through the separation column. The thus obtained chromatogram has peaks corresponding to the consumptions of the components to be detected in the liquid mixture.According to the present invention the unpractical problem that a very trace amount of a liquid sample has been so far injected when a flow rate of the eluting solution is low can be completely solved.