Structural design requirements for very large floating structures(VLFS) are different corresponding to this purpose and structural type. In this study, the structural design procedure of VLFS is described, composing of the following processes : construction of design conditions. choice of structural types and main materials, estimation of structural design loads, determination of structural arrangements, and scantling of structural members. As an example of practical application, the initial structural design of floating airport and container terminal for Pusan is demonstrated.