one of the most commonly used techniques to reduce the corrosion rate of rebar in concrete is addition substances named corrosion inhibitors into the concrete. corrosion inhibitor is chemical compounds that were added to concrete to prevent corrosion of steel in concrete. sodium nitrate is a type of anodic inhibitors that this study investigatesthe effect of this inhibitor on the properties of self-compacting and normal in condition of oman sea.to investigate the effect of sodium nitrate on properties of concrete, sodium nitrate mixed in concrete with 2%, 3%, 4%, 5% and 6% by weight of cement and samples cured in 4 environment conditions: normal water, sea water, tide condition and waste environment.the compressive strength test in age of 28 & 90 days, water absorption and water penetration in age of 90 days and accelerated corrosion test during 50 days have been done on samples.corrosion potential is measured on a daily basis. the resultsshow thatwith addition ofsodium nitrate,compressive strengthhas decreasedof7 to20%compared to thecontrol sampleresistance.water absorption andwaterpenetrationwith theaddition ofsodium nitrateis reducedin bothtypesof concrete, so that theminimumwater penetrationhasreportedfor example contains6%sodium nitrate.this studyshow positive effect of sodium nitrateon corrosion ofrebarinconcrete examplesof both type of concrete.the leastamount ofrebarcorrosionhas been observedinsampleswith3%sodium nitrate of self-compacting concrete, and insampleswith4%sodium nitrate for ordinary concrete. also the most damaged environment for concrete is tidal environment.