The present invention discloses 
tuna bone 
powder and a preparation method thereof. High-quality 
tuna bones are repeatedly washed clean and drained for a standby application, then a subcritical water combined 
microwave treatment is used to enable fish bones to be fully softened, then after the fish bones are evenly mixed with a 
deodorant, putting still is conducted for 10-30 min, then the deodorantis washed clean with 
clean water, and finally the fish bones are dried, pulverized and sterilized to obtain the 
tuna bone 
powder. The subcritical water combined 
microwave treatment technology is usedfor 
processing the tuna bones, can effectively shorten 
softening time, enhances a 
softening effect, and reduces 
time cost loss. At the same time, the preparation method retains 
calcium, 
phosphorus and other nutritional components in the fish bones to the maximum extent, and avoids caused loss and waste of nutrients during the 
softening process. In addition, after the subcritical water combined 
microwave treatment, the preparation method lays foundation for late-stage deodorization, 
drying and pulverization, can effectively release minerals of hydroxyapatite, etc. in the fish bones, significantly increases 
protein content in the fish bones, and enables nutrients in the 
fine powder to be more liable to be digested and absorbed by 
human body.