Disclosed is a submerged hollow fiber membrane module which is easy to expand, has a small installation area, and exhibits excellent contamination prevention and durability. The submerged hollow fiber membrane module comprises: (I) a module body divided into two portions which has a permeated water collection space (5) and a permeated water outlet (3); (II) module support tubes (17) which are vertically connected to the upper and lower ends of the module body; (III) a plate type module header insertion layer which is provided with hollow fiber membrane spaces (10), and is inserted into the module body; (IV) a plate type diffusion layer which is provided with a diffusion port (4) and diffusion tubes (11) and is inserted into the module body subsequent to the module header insertion layer; and (V) module headers which are inserted into the module header insertion layer.