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Pipelines have been widely used in ships and offshore structures (like drilling platforms, FPSO and subsea production systems, etc).Standards and codes are not well established for the optimal allocations of seismic restraints in pipeline systems of ships.With the applications of powerful engines and the improvements on productivity, pipelines installed in ships suffer from high vibration levels.The numbers and allocations of the seismic restraints can greatly affect the dynamic stress distribution, deflection, fatigue life and the pipeline construction costs.Therefore the corresponding optimization models and design methods should be conducted to prevent pipeline damages due to vibration.In this paper, two kinds of comprehensive seismic restraints allocation optimization design models considering strength, stiffness, buckling, eigen frequency and vibration level difference constraints are proposed.The code-based and the geometry optimization-based design methods are presented and compared.According to the presented methods, the initial numbers of seismic restraints can be defined by ASME B31 Code, or by random assumptions.Then the locations of each restraint are obtained by geometry optimization.An iterative procedure was employed in solving the presented optimization models, in which an adjustable searching step is adopted to determine the critical distance of the neighboring restraints.The criteria of the deletion and adding of the seismic restraints in pipeline depend on the satisfaction of behavior constraints and the value of critical distance.After optimization, the optimal numbers and locations of the seismic restraints in pipeline are obtained.Engineering design examples showed the effects of different choices of the objective functions on the optimal results, like construction costs, the maximum deflection, and the structural strain energy of pipelines.The effectiveness and simplicity of the proposed methods in engineering design are also demonstrated.