Abstract: The main objective of this study was to determine the parasitic infections of aquarium fish in the North of Iran. Here, 360 apparently healthy ornamental fish from 6 species (each species 60 specimens) including: Guppy (Poecilia reticulate), gourami (Osphronemus gouramy), Swordtail (Xiphophorus hellerii), Platy (Xiphophorus maculates), Brachydanio rerio and barbs (Barbus tetrazona) was obtained from a local ornamental fish farm in the North of Iran during 2012-2013. Each fish was inspected and examined by routine methods. The parasitical infection was studied by sampling from different organs. Among 360 investigated ornamental fish, 328 fish (91.1%) were infected by at least one parasite species. In this study, 5 different genus including: Ichthyophtirius multifilis, Dactylogyrus, Gyrodactylus, Tricodina and Capillaria sp. were collected from 6 species. Also, Capillaria sp. was reported as a first record from the abdominal cavity of O. gouramy in Iran.