Based on the data collected in 7 sampling stations of Chongyang River in 2007-2008, fish species，dominant species，normal species，fish ecological types and fish biodiversity in Chongyang River were analyzed. Fishes of 5 orders, 17 families, 65 genera and 73 species were collected in Chongyang River. Liobagrus anguillicauda is protected fish of Fujian Province and Leptobotia tientaiensis compressicauda Nichols，Crossostoma stigmata，Vanmanenia gymnetrus Chen，Crossostoma fascicauda Nkhols，Pseudogastromyzon fasciatus are endemic species in Fujian Province. Fish community through IRI indexes were anaylazed, Acrossocheilus hemispinus，Distoechodon tumirostris Peters，Zacco platypus，Pelteobagrusfulvidraco，Sinibramamacrops were the dominant species .The ecological types of the fish consisted of mid down fishes、omnivorous fish and adapting to lotic fishes mainly. Three diversity indexes which are Shannon Wiener diversity index(H′), Margalef diversity index(D), Evenness index(E) are used to analyze the characteristics of species diversity. Shannon Wiener diversity index in Station 7 is much higher than others in Chongyangxi River of Mingjiang watershed and then fish community structure is more stabilized than others in ralation to complicated riverbed geology and huge runoff possibly.