Concrete is the most widely used building material, and its electrical index test has received more attention in recent years. The samples of different mix proportions (water-cement ratios, sand rate, accelerator) were made and tested by impedance analysis. The results show that the impedance analysis method can eliminate the polarization effect and test the electrical properties more stably; With the increase of age, the relationship between electrical conductivity and water cement ratio gradually changed from positive correlation to negative correlation; The conductivity of the sample with accelerator was slightly higher than that without accelerator; The electrical conductivity of concrete is basically negatively correlated with the sand content. There is no order of magnitude difference in the electrical index of concrete in the concrete mix ratio, and the difference gradually decreases with the increase of concrete age. The experimental results can provide reference for electromagnetic detection work.