In order to effectively protect library collections from damage, it is necessary to know the ecology and etiology of the insects, their development, places of their location in book storages, the connections of insects with the natural environment as well as the peculiarities of the book storages (situation and location, collections movement, the volume of book charges, readers'attendance, the character of the library materials). The availability of sufficient information allows for planning measures aimed at the extermination of the vermin and prevention of library contamination.