Common carp [Cyprinus carpio L.] eggs in fish hatcheries can be severely infected by water molds, especially Saprolegnia. The current study was conducted to investigate the efficacy of alcoholic turmeric [Curcuma longa L. extract as a prophylactic measure to prevent infection during the incubation period instead of Malachite Green as an eco-friendly method. Fungi were isolated and identified during the treatment time of the artificial propagation spring season of carp fish 2021; Curcumin was extracted from turmeric [Curcuma longa L.] by silica gel column for the removal of essential oil, and its concentration was determined and compared with the standard by HPLC. The percentage of infected eggs, non-infected eggs, hatching eggs, and larvae survival rate after seven days of incubation were estimated. Saprolegnia spp. were isolated and identified depending on their morphological features. Deferment concentrations of Curcumin were used [250,500 and 1000] mg\L. There is no significant difference between treatments, but all concentrations are significantly different from Malachite Green. The percentage rate of infected eggs was 0.9±2.2, and non-infected eggs were 98.8±0.4 hatching rate was 55.3± 1.4, and larvae survival rate was 90.4±1.7. Alcoholic extract of Curcumin proved its efficacy as an eco-friendly compound to be successfully used as a prophylactic treatment of carp eggs in the hatchery.