This study was carried out to evaluate the inhibitory effect of aqueous, ethanolic and methanolic extracts of the cladodes, flowers and fruits cactus plant (Opuntia ficus-indica) with concentrations of (125, 250, 500, 1000) mg/ml against the isolation of Aspergillus niger fungus and compared it with aqueous solution of antibiotic (fluconazole) at concentration 10 μg/ml. The study showed a difference in efficacy of studied extracts in inhibiting the growth of studied fungus, The methanolic extract of flowers showed higher inhibiting ratios (76.86, 81.32) % at concentrations (500, 1000) mg/ml respectively, followed by the methanolic extract of cladode by inhibiting ratios reached (73.49, 76.14) % at the previous concentrations, then followed by the ethanolic extract of flowers by inhibiting ratio (40.96, 57.83) % at the same of previous concentrations, while inhibiting ratio of fluconazole reached 65.66% at the used concentration, whereas the aqueous extracts of flowers, fruits and cladode had the lowest effect by inhibiting ratios reached (36.74, 23.49, 12.53) % respectively at concentration 1000 mg/ml.