CD spectra of alginate gels prepared under various methods were measured, and correlationbetween the preparation methods and structure of the prepared gels was organizedalong with the knowledge in the reported studies. Ca type, Fe type and Acid typealginate gels were prepared in this study. Acid gels were prepared in HCL or GDL (gluconicacid-δ-lactone). solutions. Ca type gel showed CD spectra that is characteristic inalginate with G segment and GG block. In the case of gels prepared with Fe3+ aqueoussolution, Acid gel was predominantly formed in dilute Fe3+ solution, and a gel showing aCD spectrum with a broad negative peak on the longer wavelength side was formed inconcentrated Fe3+ solution. When contacting with Ca2+ ions and Fe3+ ions, the Acid gelshowed CD spectra similar to Ca2+ type and Fe3+ type gels type gels, which indicatedthe change in network structure of Acid gel from hydrogen-bonded network structureto the structurally stable ion binding one.