The invention relates to a four hole-type circular truncated cone-shaped mud flat combined constructed reef. The four hole-type circular truncated cone-shaped mud flat combined constructed reef is composed of single fish reefs, middle connecting beams and middle connecting beam support vertical piles, wherein every single fish reef is composed of a circular truncated cone, a cross beam and vertical piles; the outer edge of the circular truncated cone is a ring, and three horizontal rods are embedded inside the ring to form an equilateral triangle; the quartering parts the bottom of the ring ofthe circular truncated cone are provided with four downward first clamping orifices for clamping the cross beam; the left and the right of the cross beam are downwards provided with second clamping orifices for matching with the vertical piles, and third clamping orifices for perpendicularly matching with neighboring cross beam; the upper end of each vertical pile is provided with a reinforced concrete square pile with a Y-shaped clamping orifice for arranging the cross beam; the single fish reefs are sequentially connected in rows; the middle connecting beams are used for connecting every two neighboring rows of fish reef groups. The four hole-type circular truncated cone-shaped mud flat combined constructed reef is stable and firm, convenient to repair, large in area of formed pools andcapable of effectively improving the biological resource quantity and providing a better living environment for living beings.