Today, various types of industrial waste are used as sustainable mineral materials to replace part of cement in concrete production with an economic approach. The main purpose of this study is to compare and evaluate the effect of using two types of slag from Isfahan Steel Plant and Esfarayen Steel Plant as a replacement of different percentages of cement in ordinary concrete, which was done in three phases. Concrete samples with mixing design and different percentages of two types of slag with water-cement ratios equal to 0.54 and 0.43 were made in the first phase and after being placed in the water pool, at the ages of 28, 56 and 90 days. were tested for compressive strength. In the second phase, concrete samples with optimal percentages of slag were made to measure the samples. Reinforced concrete beams with dimensions of 1000 × 150 × 150 mm with 3 different mixing designs in the third phase and to check the structural performance of concretes containing optimal percentages of slag were made and a four-point bending beam test was performed to obtain the Ultimate capacity. became. The results of the tests showed that although the strength of concrete samples containing different percentages of slag at the age of 28 days was lower than that of normal concrete, but the strength of concrete samples containing 30% of Isfahan slag and 20% of Esfarayen slag at the age of 56 and 90 days was almost equal to normal concrete. And resistance was the goal. The results of the durability tests in the second phase showed that the durability of samples containing slag in sulfate environment was more than normal concrete. Also, the ultimate bending capacity of reinforced concrete beams containing 30% of Isfahan slag and 30% of Esfarayen slag showed a 10% increase and a 3% decrease, respectively, compared to the beam without slag.