A method for producing vitamin K2 comprising: culturing Bacillus natto in a liquid medium to obtain a Bacillus natto culture or culture supernatant thereof, wherein the culture or culture supernatant contains vitamin K2; treating the culture or culture supernatant with at least one coagulant selected from the group consisting of an inorganic coagulant and a cationic polymer coagulant, with the proviso that the coagulant excludes chitosan, so as to obtain a treated coagulant to which vitamin K2 is absorbed or aggregated; separating the treated coagulant from the treated culture or culture supernatant, and obtaining an oily product that contains vitamin K2 from the separated coagulant.