In order to obtain stable and high-quality sequential images under transient condition and different object distances, a four-channel sequential front light high-speed imaging system was designed. The system used image space parallel light splitting, taking the imaging principle as the starting point to analyze the key design elements of system. Based on the theoretical calculation parameters, the sub-lens groups (objective lens group, field mirror and collimating lens group, converging lens group) was designed and aberrations were independently corrected. Adding field mirror to reduce the size and weight of system and improve light energy utilization. The transmission effect of beam was improved by accurate connection of field of view and pupil. On this basis, the sub lens groups were integrated and optimized, and beam splitters were added to form the final four-channel sequential front light imaging system. The object distance adjustable optical path was designed, and the image quality of system at the object distance of 0.5 m~∞ was guaranteed by adjusting the handwheel of objective lens group in use, while keeping the position of primary image plane unchanged, enhancing the stability of system performance stability and reducing the difficulty of installation and adjustment. The receiving part of system can be replaced according to actual needs, and the system can be expanded to eight-channel system after adding splitters in the beam splitting region. The installed and adjusted sequential front-light imaging system is used for laboratory testing and field tests, and main optical performance is good. the resolution of each channel can reach 72 lp/mm, and imaging consistency is greater than 98%. Field test results show that the optical system can meet the requirements for shooting sequence images under transient condition.