There is a few book on a family of mites which be comprehensive like this book. Mites of this family are associated with main orders of Insects, i. e. Hemiptera, Lepidoptera, Orthoptera and Isoptera which are important in the agriculture. Most members of the family are ectoparasites. This book includes detailed morphology and systematics of Otopheidomenidae as well as comments of the author. Experience is very important in systematics and the author, Dr. Vikram Prasad is published this book after his many year works on otopheidomenids. Morphology is discussed in detail including all parts of the body which I have never seen before in any reference and in systematic part, diagnosis and redescription for many species, some key morphological characters, and chaetotaxy of ganua and tibiae I-IV (See Figs. 1– 3, gnathosoma), and remarks or note for each species as well as some keys are presented. A key is included to identify the 12 species of Otopheidomenidae belonging to two subfamilies (Otopheidomeninae and Prasadoseiinae subfam. nov. ). Another key is provided for identification of seven families of Phytoseioidea (Blattisociidae, Hemipteroseiidae fam. nov., Katydiseiidae, Otopheidomenidae, Phytoseiidae, Podocinidae and Treatiidae) as accepted in this work. Eickwortius termes Zhang and Orthopteroseius sinicus Mo are transferred to Blattisociidae. Genera Nabiseius with four species and Treatia (Syn.: Entomoseius) with four species are included in the family Treatiidae...