This study invesyigates the digestive system of freshwater mite, Unionicola aegyptiaca which starts with an anteroventrally mouth opening and ends with a posterodorsally anal opening. This system occupies a major portion of the body cavity and consists of three main parts: the foregut (mouth, muscular pharynx and oesophagus), the midgut (ventriculus with its associated three pairs of gastric caeca) and the hindgut (rectal tube and rectum). A pair of salivary glands is situated ventrolaterally in the anterior end of the body cavity. The main excretory system of the present freshwater mite consists of a pair of elongated Malpighian (excretory) tubules which extends along the length of the body. The nervous system of the present species consists of a central nerve mass (brain) with several nerve trunks that branched to supply nerves to various body parts. The brain is separated into two regions: supraoesophageal and suboesophageal nervous masses.