Corrosion rate data of metal materials for construction; particularly carbon steel used in wet environments containing NaCl, is very important due to safety reasons. It is, therefore, necessary to investigate the corrosion rate of construction steel in various NaCl concentrations. The objective of this work is to study the corrosion rate of low carbon steel by varying the concentration of NaCl in distilled water, using a loss of weight method. To carry out this research, 25 low carbon steel samples, of 80x24x3 mm sized coupons, were made. Samples were divided into 7 treatment groups, and weight loss measurements were carried out for 240, 480, 720, 960, 1200, 1440 and 1750 hours, respectively. Experimental data was obtained by totally exposing the samples to NaCl solutions of 2%, 3%, 4% and 5%, and one treatment in distilled water only. The results show that NaCl concentration significantly influenced the corrosion rate for all solution variations. The most obvious effect was observed in the first 240 hours of exposure time for all concentrations of NaCl; which then gradually decreased until an exposure time of 1750 hours was reached. The average corrosion rate value was0.2427 μm/year.