Cocoons of silkworm Bombyx mori L. were irradiated with four different doses of gamma radiation; 10, 20, 40 and 60 krad to minimize the damaged occurred during storage.  Irradiated cocoons were packaged in different kinds of sac materials as traditional gunny, polypropylene, printed paper, thick paper, thin and thick cotton textiles treated with chamomile and propolis powder to overcome. Pest infestation preservation period was six months with one month as investigation interval.  Packages of thick paper and thin textile treated materials gave the best results for preservation of cocoons irradiated with higher doses of gamma radiation gave the best results. as there were no resulted damaged cocoons through six months preservation period. Infestation test was carried out by irradiating adults of Dermestes maculates with 10 krad dose of gamma ray and transferred into the treated packages made of different kinds of sac material to investigate their ability for infesting silkworm cocoons.  The lowest percentages of damaged cocoons were recorded when irradiated adults infested cocoons stored in thick paper, thin and thick cotton textiles treated packages.  Generally the highest damaged cocoons percentages were scored when cocoons preserved in packages made of traditional gunny, polypropylene and printed paper.