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Settlement of benthic community depends on environmental conditions and interspecific reactions. The effect of substrates on the surface cover by the soft coral, Zoanthus sansibaricus, and the brown algae, Iyengaria stellata and their computational condition, was compared in the Hormuz Island by estimating of coverage area in 40 quadrates (50×50 cm). Z. sansibaricus is a dominant soft coarl (Zoanthid) species in Hormuz island coasts in the other side I. stellata considered as dominant macroalgea, most of year in area. Significant negative correlation (p<0.01; r = -0.607) revealed competition between two species in settlement on the two substrates. Soft coral with 61.7% coverage was dominant vs. 16.8% for brown algae on muddy-Rubble substrate, but on sandy-Rubble substrate, the brown algae was dominant with 37.8% coverage vs. 19.5% for the soft coral. It seems that better compitiunal conditions in settlement on unconsolidated substrate have some advantages for Z. sansibaricus on Muddy-rubble substrate.