：316L austenitic stainless steel has excellent corrosion resistance，but due to the high price of Ni，in order to reduce smelting costs，the Ni mass fraction is controlled at 10. 00%-10. 30%. This 316L stainless steel with a Ni content at the lower limit of GB/T 20878—2024 is called low-nickel 316L. The morphology and distribution charac⁃ teristics of ferrite in low-nickel 316L austenitic stainless steel continuous casting slabs was investigated. The varia⁃ tion in ferrite content and morphology across different slab positions was analyzed through microstructure character⁃ ization，element segregation analysis，and thermodynamic calculations. The influence of cooling rate on ferrite was further examined via remelting experiments. Samples were sequentially extracted along the slab thickness direction. Ferrite morphology evolution，content，cooling rate，and element distribution were studied using metallographic observation，electron backscatter diffraction（EBSD），and electron probe microanalysis（EPMA）. The effect of cooling rate on ferrite content was assessed through remelting experiments under different cooling conditions. The solidification mode was determined using Thermo-Calc thermodynamic calculations. Results reveal an "M"-type distribution of ferrite content along the slab thickness. Ferrite content increases from 7. 52% at the surface to 11. 20% at 50 mm depth，then decreases to 6. 98% toward the center. The ferrite morphology evolves systemati⁃ cally with increasing distance from the surface，transitioning from skeletal/lath-like to block-like and mesh-like， finally forming short rod-like shapes at the center. Secondary dendrite arm spacing increases from 21. 37 μm（sur⁃ face）to 63. 67 μm（center），corresponding to a cooling rate decrease from 6. 69 °C/s to 0. 38 °C/s. Thermodynamic calculations confirm an FA（Ferrite-Austenite）solidification mode，where ferrite forms first. Element segregation analysis indicates Cr and Mo enrichment in ferrite，while Ni concentrates in austenite. In remelting experiments，water-cooled samples exhibit 22. 40% dendritic ferrite，whereas furnace-cooled samples contain 2. 71% short rodlike and strip-like ferrite. A small amount of Chi phase is also observed in the furnace-cooled sample. The "M"-type ferrite distribution results from the combined effects of cooling rate on initial dendrite spacing and solid-state phase transformation.