In this study, we aimed to describe the morphological and molecular characteristics of Austroglycyphagus geniculatus (Acari: Glycyphagidae) breeding in fodder. Flour and corn-crushed fodder samples were collected from a small fodder processing mill in Wuhu, Anhui province, China. The detection rate of A. geniculatus was 100% in six samples, and the breeding density was 1.44 mites/g. Under an optical microscope, we observed that the mite body was oval and small in size. The epidermis of the mite was coated with fine particles. We found two obvious, large, and red lateral ventral glands on either side of hysterosoma. The gene sequences for internal transcribed spacer (ITS) and mitochondrial cytochrome oxidase 1 (COX 1) of A. geniculatus were amplified and uploaded to the GenBank nucleotide sequence database. To the best of our knowledge, this is the first study to report the detailed description of the morphological and molecular characteristics of A. geniculatus. The results of phylogenetic relationships obtained from the ITS and COX 1 support the classification statuses of A. geniculatus to the family Glycyphagidae based on the morphological classification. Our study provides morphological and molecular data for inferring phylogenetic relationship of A. geniculatus.