A modified double-split ring resonator and a modified triple-split ring resonator,which offer polarization-insensitive performance,are investigated,designed and fabricated.By displacing the two gaps of the conventional doublesplit ring resonator away from the center,the second resonant frequency for the 0° polarized wave and the resonant frequency for the 90° polarized wave become increasingly close to each other until they are finally identical.Theoretical and experimental results show that the modified double-split ring resonator and the modified triple-split ring resonator are insensitive to different polarized waves and show strong resonant frequency dips near 433 and 444 GHz,respectively.The results of this work suggest new opportunities for the investigation and design of polarization-dependent terahertz devices based on split ring resonators. A modified double-split ring resonator and a modified triple-split ring resonator, which offers polarization-insensitive performance, are investigated, designed and fabricated. By displacing the two gaps of the conventional doublesplit ring resonator away from the center, the second resonant frequency for the 0 ° polarized wave and the resonant frequency for the 90 ° polarized wave became increasingly close to each other until they are finally identical. theoretically and experimental results show the modified double-split ring resonator and the modified triple-split ring resonator are insensitive to different polarized waves and show strong resonant frequency dips near 433 and 444 GHz respectively.The results of this work suggest new opportunities for the investigation and design of polarization-dependent terahertz devices based on split ring resonators.