Ion Chromatography (IC) has undergone a tremendous development and can be regarded today as one of the most versatile analytical methods for all kinds of ionic compounds. The IC technique offers an enormous range of possibilities for the selection of stationary and mobile phases, fabrication of novel separation modes, and hyphenation with different detection techniques, which has made IC eminently suitable for the rapid and simultaneous determination of numerous inorganic and organic anions and cations. In this paper, firstly, a general overview of the IC principle, including the IC methodology, development history, separation mechanism, apparatus and procedure, and application, is given as an introduction of this technology. Secondly, the significant role of sample preparation for IC is discussed, and various IC sample preparation methods are summarized. Finally, the currently practiced advanced IC techniques for complicated samples, critical analytical requirements and unique application are presented, which mainly focus on the two-dimensional IC technique (2D-IC), hyphenation technique of IC with mass spectrometry (IC-MS) and capillary IC technique (CIC).