An artificial hexagonal frame reef comprises a lower frame constituted of three hexagonal frames respectively radially disposed in sequence on a concentric circle, vertical post frames respectively installed at corners of the lower frames, two step slanted frames extending substantially upward from an upper end of a perimetric post frame beyond upper ends of a middle post frame and an inner post frame in sequence, a middle layer frame and an upper layer frame installed on the slanted frames in a hexagonal shape so as to form a pyramid-type artificial steel reef, a lower wall frame which is installed between the lower frame and a middle layer frame and which has a shape of window frame, and an upper wall frame which is installed between the middle layer frame and the upper layer frame and which has a shape of window frame. The reef is capable of effectively preventing the artificial reef from being sunk, improves fish gathering effects by providing a visual attracting effect, improves the structural stability of the artificial steel reef, and can lead to the benefit of gentle tidal current in the space essential for the growth and development of various aquatic plants and various marine fishes which is created in the center portion of the artificial reef, and is capable of providing various aquatic plants and various marine fishes with optimum environmental conditions. [FIG 1] 4a 10 14b 16a1 8 16b2 5 15a 15b a6 7a 1
