The invention belongs to marine 
functional food and particularly relates to marine 
functional food capable of inhibiting prostatic 
cancer. The marine 
functional food belongs to a 
squid ink polypeptide 
active matter prepared through extracting 
squid ink by an acid method. A specific method comprises the steps that 
hydrochloric acid is added into the preprocessed 
squid ink, the leaching is carried out under the conditions that the 
hydrochloric acid concentration is 0.02 to 0.03 mol / L, the acid lifting material 
liquid ratio (the volume ratio of double 
distilled water to 
raw material squid ink) is 1:(1-2), the acidolysis time is 2 to 3 hours, the acidolysis temperature is 35 DEG C to 40 DEG C, finally, the leaching liquid is centrifuged to obtain 
clear liquid, and the obtained 
clear liquid is the coarse squid ink polypeptide 
active matter. Rich marine biological squid ink is adopted, the squid ink polypeptide is purified by methods of acid method extraction, concentration and the like, in addition, the optimal acidolysis process is obtained through an orthogonal test, and the most squid ink polypeptide active matters are obtained. CCK-8 method detection shows that the squid ink polypeptide has the obvious proliferation inhibition effect on DU-145 and PC-3 cells of the prostatic 
cancer, can inhibit the DU-145 and PC-3 
cell proliferation and can induce the 
apoptosis of the cells, so the prostatic 
cancer is inhibited.