Species of the genus Cryptosporidium (phylum Apicomplexa) are zoonotic protozoan pathogens, able to infect the epithelium of the gastrointestinal tract of a wide range of invertebrate and vertebrate hosts, including humans. There is  limited knowledge regarding theLittle known about the geographical distribution, prevalence, and the epidemiology of Cryptosporidium isolates of Cryptosporidiuminfecting fish. In the past 20 years, several studies have focused on Cryptosporidium in fish. To date, four species (Cryptosporidium molnari, Cryptosporidium huwi, Cryptosporidium scophthalmi and Cryptosporidium abrahamseni) have been identified as piscine-host-specific, nine piscine genotypes and more than 29 unnamed genotypes have been described in fish hosts. In addition, other non-piscine-host-specific Cryptosporidium species (C. parvum, C. hominis, C. scrofarum, C. xiaoi) have been genetically characterized in fish. While the presence of Cryptosporidium zoonotic subtypes in edible fish increases the risk of fish-borne zoonotic infections, which is significant from the perspective of public health, the pathology of cryptosporidiosis is very important for the aquaculture industry because since it causes mortalities in farmed fish. Understanding the dynamics and transmission channels of Cryptosporidiosis infection is critical; but however, none of the laboratory diagnostic techniques such as acid fast staining and direct or indirect immunofluorescence microscopy can differentiate between the species or subtypes of the parasite. These days, the polymerase chain reaction (PCR) is used more often as a diagnostic technique to identify and classify species and track the parasite's numerous pathways of transmission. Thus, the history, biology, pathology, and clinical symptoms of Cryptosporidium in fish from freshwater and marine environments are gathered up in this review in conjunction with the prevalence, and molecular epidemiology of the disease. In addition, data on how piscine hosts may act as a reservoir for zoonotic Cryptosporidium species were included.