The amount of bacteria in fish pond was plenty and changeable.The sequence of the total amount of bacteria was summer,autumn,spring and win-tar. In water, the organo raphs were more ixi summer, while in bottom-mud theywere more in autumn. The amount of erganotrophs and the total amount of bacteria,were correlated positively to the chemical oxygen demand (CCD). The fatal amountof bacteria showed a positive correlation to water temperature, but the organotro-phs were not. The total amonut of bacteria and organotrophs were not correlated tothe plankton biomass, but the total amount of bacteria were correlated to the zoo-planlton biomass. The suitahle pH range for growth is 6.4-9.4. The power of thecommon fisheries medicines reducing the amount of bacteria wars in order of bleeding powder>CuSo,FeSo,mixture>dipteregx