In experiments of pulsed laser-matter interaction, pre-pulse with higher peak power interacting with matter produces a plasma that corrupts the experimental results. To avoid this problem, it is necessary to reduce the peak power of the pre-pulses. Therefore, it is necessary to find a way to improve the temporal contrast of the pulsed laser, which is also the main purpose of this paper. When using chirped pulse amplification technology to design femtosecond Ti: sapphire regenerative amplifier with high peak power, on the one hand, the amplified spontaneous emission in the amplified laser will be amplified before the seed light, so the temporal contrast of the amplified spontaneous emission of the amplified laser will be low; on the other hand, due to the low extinction ratio of the polarization selective device in the amplifier, the pre-pulse temporal contrast of the amplified light will be low, both of which will lead to low temporal contrast of the amplified light.In order to improve the temporal contrast of laser pulse output by regenerative amplifier, it is necessary to improve the temporal contrast of nanosecond and temporal contrast of picosecond laser pulse simultaneously. On the one hand, this paper studies the influence of a compact dual-channel pulse cleaner for the Pockels Cells on nanosecond pre-pulse temporal contrast, through this device, two laser pulse cleaning can be completed on a set of the Pockels Cells which makes the pre-pulse temporal contrast of regenerative amplifier by 5 orders of magnitude. On the other hand, the influence of the position where the regenerative amplifier is inserted into the spectral shaping filter on laser pulse amplified spontaneous emission contrast is studied. By inserting the spectral shaping filter in an appropriate position in the ring cavity and adjusting the angle of the spectral shaping filter, the position with the lowest actual transmittance of the spectral shaping filter is just the position with the strongest amplified spontaneous emission spectral intensity in the ring cavity. It is shown that amplified spontaneous emission can be reduced by 1 order of magnitude in the range of a few hundred picoseconds. The pre-pulse temporal contrast ratio is enhanced from the original 4.3×10^-4 to 6.6×10^-10, and the amplified spontaneous emission temporal contrast ratio (400 ps before the main pulse) is improved from 5.0×10^-8 to 5.0×10^-9.This optical system which includes both dual-channel pre-pulse cleaner and intracavity spectral filtering has the following advantages: the dual-channel pre-pulse cleaning devices using only a single Pockels Cells is placed at the optical outlet of the amplifier. This device not only greatly increases the pre-pulse temporal contrast of the laser pulse, but also effectively reduces the volume of pre-pulse cleaning device, avoiding the redundancy of optical elements and the space waste caused by the additional pre-pulse cleaning device, thus reducing the cost. Then, instead of changing the seed light energy, the amplified spontaneous emission contrast of the laser pulse output by the regenerative amplifier is improved by adding a spectral shaping filter at a suitable position in the cavity. This method not only effectively suppresses the problem that the amplified spontaneous emission in the amplifier cavity is amplified, but also suppresses red shift and gain narrowing of the spectrum during the amplification process. This process simultaneously achieves the purpose of outputting a broad-spectrum laser pulse and enhancing the temporal contrast of the amplified laser. In addition, adding a spectral shaping filter in the cavity can effectively improve the energy stability of the amplified laser. The above scheme comprehensively improves the temporal contrast and stability of laser pulses output by the regenerative amplifier, and provides high-quality seed light for subsequent laser energy amplification.