Abstract: Using the theory of the partial reflection, the formation of longer echo tracing of the Es layer is investigated with data detected by the European incoherent scatter radar and ionospheric dynasonde. Based on the theory of wave propagation in the layered media, we firstly calculated the partial reflection coeficient of the Es layer, and then used the experimental data which measured by the incoherent scattering radar to calculate the echo tracing and compare with the experimental data. The result shows that the Es layer ionogram traces by the theory of partial reflection agrees well with the experimental data.