Disclosed is an effective prophylactic/therapeutic vaccine which can protect from scuticociliatosis, particularly can protect from the infection by Philasterides dicentrarchi that has a high mortality rate. The vaccine comprises (1) an inactivated product of a strain having the same serum type as that of P. dicentrarchi strain Iyo I, (2) an inactivated product of a strain having the same serum type as that of P. dicentrarchi strain Nakajima, and (3) an inactivated product of a strain having the same serum type as that of P. dicentrarchi strain Mie0301 as active ingredients.
