This work was conducted as a part of the preliminary study on the mass culture of Pseudaphycus malinus Gahan, an important parasite of Pseudococcus comstocki (Kuwana). The author dealt with the low temperature storage of the mummies in which the parasites were either in the prepupal or pupal stage. The experiments were carried out for the purpose of examining the developmental stage of the parasite most suitable to the low temperature storage, the period of the mummies without lasting the ability to emerge, the period from the exposure of the stored mummies to the higher temperature of 25℃ to the emergence of the parasites from them and the stage of the parasite having high mortality in the mummies. In the first experiment, the mummies which were formed at the temperature of 25℃ were transferred to the lower temperatures and stored at 8, 10 and 12℃ (±1℃), separately. In this case, the mummies stored at these temperatures were separated by the developmental stage of the parasite into the following three stages. First stage was 1 day after the mummies were formed; most of the parasites in the mummies were in the prepupal stage. Second stage was 3 to 4 days after the mummies were formed; the parasites were either in the prepupal or pupal stage. Third stage was 8 to 9 days after the mummies were formed; all parasites were in the pupal stage. In the second experiment, the mummies which were 1 to 4 days after they were formed were stored at 8, 10 and 12℃, separately. The method of this experiment after the exposure of the mummies from the low temperature to 25℃ were similar to that mentioned in the first experiment. As the result of the first experiment, the per cent of the emergence of the parasites from the mummies decreased with the length of the storage and also varied with the developmental stage of the parasites when the exposure of the mummies at the low temperature was started. The highest per cent of the emergence of the parasites from the mummies stored for 90 days was gained especially in the mummies which were stored at 10℃ 1 day after they were formed. In the second experiment, the last emergence of the parasites was confirmed in the mummies stored for 160 days at 10℃. The period from the exposure of the mummies stored to 25℃ to the emergence of the parasites was between 11 and 16 days, However, even in the mummies stored at 12℃, some parasites had emerged during the low temperature storage and the period mentioned above was 4 to 11 days. The facts that the parasites emerged from the mummies stored for a long period were very few seem to be attributed to the prompt temperature change from the cold storage chamber of about 10℃ to the emergence room of 25℃ and the low humidity in the cold storage chamber.