Abstract: Since the launch in 2017, Insight-HXMT (Insight Hard X-ray Modulation Telescope) has been one of the most important astronomical satellites for accretion X-ray pulsar studies due to its wide energy band, the large effective area and the high observational cadence, which has achieved fruitful research outputs. The aim of this paper is to review and summarize key breakthroughs related to accretion processes and cyclotron resonant scattering features in accreting pulsars, mainly including the detection of high energy cyclotron absorption lines, the evolution of cyclotron line energies, and the study of radiation-pressure-dominated accretion disks.