Suction anchors or suction pile anchors are one of the most common foundation systems for floating structures in offshore because of their convenience in construction. As the offshore structures become larger and come to locate in deep water, the demand on mooring-anchor systems with large capacity is also increasing. To enhance the horizontal capacity of suction anchor, in this study, multiple types of suction anchor are introduced inwhich two single suction anchors are connected side by side using plate in longitudinal direction. Under different dimensions of single suction anchors (D=1.0, 3.0, 5.0, 7.0 m; L/D=1, 2, 3 for each diameter condition;D=Diameter, L=Length), three types of multiple suction anchors are suggested inwhich the distance between two single anchors varies 0.5D, 1.0D, 1.5D. Horizontal capacities for each type of suction anchor are obtained by numerical simulations using Abaqus/standard, and the results are presented by a chart having axes of diameter and horizontal capacity. Two soil conditions, silty sand with Mohr-Coulomb yield criterion and clay withTresca yield criterion, are applied in numerical analysis, and the charts for each soil condition are suggested.