The invention provides a quick freezing pupa killing method for fresh silkworm cocoons, particularly comprising the following steps that: solid dry ice is taken as a cold source to absorb heat of the fresh silkworm cocoons, and simultaneously carbon dioxide obtained through sublimation of the dry ice is taken as the cold source to blow over the fresh silkworm cocoons and exchange heat with the fresh silkworm cocoons so as to make the temperature of the fresh silkworm cocoons reduced to below a given temperature and maintain for a period of time. The invention simultaneously provides a device for realizing the method, comprising an insulated cabinet body and an endless apron, wherein, a cold source cabinet body is arranged on the upper part of the insulated cabinet body, and the solid dry ice is arranged inside the cabinet body; the bottom of the cold source cabinet body is provided with a heat exchange plate; a cold blast pipe is arranged on the lower side of the endless apron, and an opening of the cold blast pipe faces to the endless apron; the cold blast pipe is communicated with the cold source cabinet body; and a fan is arranged on an inlet end of the cold blast pipe. By adoption of the method and the device, the pupa killing production cycle can be obviously shortened and the labor efficiency can be obviously improved; moreover, because pupae are killed at a low temperature, fresh cocoon shells and pupal cells maintain natural state, thereby the quality of the fresh cocoon shells and the pupal cells is slightly influenced and good-quality raw materials are provided for the silk reeling technique and deep-processing of fresh pupae.