A new device for dispersion compensation of ultra-short laser pulses is developed. This setup is made up of a pair of double-line-density grisms. Each grism consists of a prism and a grating separated from each other. It is featured that the density of the second grating doubles the first one′s. The numerical results of ray tracing show that this setup can compensate third-order dispersion independently without any spatial distortion, and the compensation sphere covers a wide scale from negative to positive. It provides a certain reference for dispersion compensation of femtosecond pulses in chirped pulse amplification systems.