In a attempt to verify a reduction characteristic in leaching for hexavalent chromium from concrete structures, concrete specimens blended with Loess additive was exposed to sea environment followed by measuring the concentration of Hexavalent chromium from the specimens. Additional experiments with respect to basic properties of concrete with Loess additive were also performed. The entire results of experiments revealed that the reduction characteristic was predominant for concrete with Loess additive and basic properties of concrete with Loess additive were comparable to that of concrete with OPC.