PURPOSE: A tunnel type multifunctional fish reef for composing sea wood is provided to obtain excellent effect as the fish reef for composing the sea wood due to a wide sticking area and to be planted on a weak ground due to a low earth contact pressure. CONSTITUTION: A tunnel type multifunctional fish reef for composing sea wood comprises: an inserting projection(30) and an inserting groove(32) which are included on an upper part of body(16) and a lower part(14) of the body； an access hole(20) which is penetrated into the upper and lower and both side part(12) of body； a coalescing rope(40) settled in a rope recess； and a shadow space pipe(50) of a cylinder pipe or a bellows pipe which is united with a plurality of access holes.
