The use of medicinal plants as natural antimicrobial agents is gaining popularity. Natural products provide unlimited opportunities for new drug leads because of the unmatched availability of chemical diversity. The aim of this study is to evaluate the antimicrobial activity of different types and part of citrus species against different microbial isolates. The antmicrobial effects of aqueous extracts of peel, juice and leaves from fresh Citrus aurantium (sour orange), Citrus sinensis (sweet orange), Citrus reticulata (tangerine, mandarin) and Citrus grandis (pummelo) against 3 Gram-positive and 6 Gram-negative bacterial, including S. aureus, S. pyogenes, E. feacalis, P. aeruginosa, K. pneumoniae, E. coli, S. typhi, Proteus spp., M. catarrhalis, all of them were studied. Citrus juices showed the highest antibacterial activity against most of the study bacterial isolates. Moderate activity produced by the citrus peels and the lowest effect produced by the extract of the citrus leaves. Different aqueous extracts from various citrus species can be used as effective antibacterial reagents even against multidrug resistant bacteria, and home-available, safe, cheap and with no side effect like the synthetic drugs.