Microwave radar non-destructive testing (NDT) technique is used to simulate and measure concrete cylinder containing rebar and void. The interaction of electromagnetic wave and concrete has been observed both by simulation and by measurement. A Finite-Difference Time-Domain (FDTD) method with Perfectly Matched Layer (PML) Absorbing Boundary Condition (ABC) is used to simulate electromagnetic wave propagation in concrete cylinder 2D simulation of a wave generated from a point source at microwave frequencies. Using both TE and TM waves for simulation, which wave is more advantageous is compared. A concrete specimen is prepared in accordance with the simulation setup and measured using a Vivaldi antenna array and vector network analyzer. The reflection and transmission coefficient obtained from the measurement and the reflection and transmission coefficient obtained from the simulation are compared.