The present invention relates to a method for separating and analyzing ions by electrostatic ion chromatography using water as the eluent not only for the analysis of the group of anions or cations but also for the simultaneous and simple analysis of the two groups of analyte ions. A solid phase packed in a separation column to be used therefor is a zwitterionic stationary phase, comprising a support carrier and a zwitterionic layer formed by directly or indirectly coating or immobilized a compound having both of a positive-charge portion and a negative-charge portion (an ammonium salt or amide portion, and a sulfonate ion portion or carboxylate ion portion) on the surface of the support carrier for detecting given separated ions by ultraviolet method etc. And another present invention relates to a method for separating and analyzing inorganic and organic components etc. simultaneously by multi-functional liquid chromatography.