The present invention relates to a method for preparing granules for a fish feed or an assorted feed aid, and more particularly, a method for preparing organic coating porous granules for a fish feed or an assorted feed aid using the blood of livestock and clay minerals. The method for preparing organic coating porous granules for a fish feed or an assorted feed aid using the blood of livestock and clay minerals, the method includes: a first mixing step of preparing plural clay minerals including a zeolite and a bentonite and then pulverizing, calcining, and mixing them respectively, thereby preparing a powder mixture； a second mixing step of preparing the blood of livestock, and then mixing the blood of livestock with the powder mixture by pulverizing, thereby preparing a fluid colloidal slurry； a molding step of jetting the fluid colloidal slurry prepared in the second mixing step at a high pressure in a granulator with an inner temperature of 130-400°C, thereby preparing granules including a granule layer having a porous structure and an organic coating layer formed outside the granule layer to wrap the granule layer； and cooling the molded granules. The present invention is to provide granules for a fish feed or an assorted feed aid, wherein the granule contains useful minerals, such as zeolite and bentonite, suitable to be used for a feed, and includes an organic coating layer mainly composed of proteins formed on a surface of the granule by using the blood (let blood) of livestock, so that the time while water infiltrates into pores inside the granule mainly composed of inorganic substances is delayed, thereby obtaining having excellent fluidity.
