Rotaviruses constitute the genus Rotavirus, one of the 15 genera of Reoviridae family. Rotaviruses, are very contagious segmented, double-stranded RNA viruses, responsible for diarrheic diseases worldwide. Within genus Rotavirus, 7 distinct groups (from A to G), as well as 4 specific subgroups within the group A, are identified. Groups A–C are found in both humans and animals, while rotaviruses of groups D–G are limited to animals. The groups A–E cause disease in animals but humans are infected, most commonly by group A. Rotavirus is the leading cause of acute gastroenteritis in infants and young children worldwide. The disease is also seen in young calves, piglets, foals, lambs, kids, cats, dogs, poultry and wild birds. The transmission route is fecal-oral and maximum virus excretion occurs 2–5 days post infection. The rotavirus replicates in the cytoplasm of the mature absorptive and enzyme producing enterocytes of small intestinal villi. Destruction of mature villi leads to rupture and sloughing of the enterocytes with release of virus and infection of adjacent cells. The clinical outcome is similar in most species, and severity of disease may range from asymptomatic or subclinical condition to severe gastroenteritis. Pertaining to humans, rotavirus diarrhea is a major cause of death of millions of infants in developing countries while in domestic animals it is inflicting severe losses to the livestock sector. Generally, rotaviruses are species-specific, but human infections with animal rotaviruses are possible. Rotaviruses can be detected in stool specimens by several techniques, including electron microscopy, polyacrylamide gel electrophoresis, antigen detection assays, RT-PCR and virus isolation. For prevention, good management practices coupled with vaccination of the dam for newborns protection, has to be practiced.