Abstract: The migration of deltaic river channels is a major factor affecting the sedimentary evolution pattern of the delta. Due to its large sediment supply and frequent channel migrations, the Yellow River Delta was regarded as an ideal area to address this issue. In this study, we systematically collected the age and particle size data from 22 sediment cores to explore the impacts of the three Yellow River channel migration events on the sedimentary evolution of the Yellow River subaqueous delta and spatial differences in the delta’s response to the same migration event. In 1855, the northward inflow of the Yellow River into the Bohai Bay caused changes in the sedimentary sources and sedimentary dynamics, resulting in refined sediment particle size and a shift in particle size frequency distribution curve. In 1976, the Yellow River was diverted from the Diaokou course to the Qingshuigou course, causing the particle size of abandoned Diaokou subaqueous delta to coarsen with increased sand content and decreased sedimentation rate. Interruption of the terrestrial supply increased the influence of marine organic matter on organic carbon burial. However, the direct supply of fine sediment from the Yellow River caused the fining of particle size seen in sediment cores in the Laizhou Bay and the active river mouth area. Since 1996, the Yellow River has been diverted to the Q8 course, causing a continuously coarsening trend in particle size in the Diaokou area; the main source of sediment in the Laizhou Bay area had changed to eroded coastal materials with coarsening particles; and the active subaqueous delta received the material supply from the Yellow River sediment, but the dynamic sorting during transportation caused a trend of particle coarsening in the shallow area.