We elucidated the effects of snow and remineralization processes on nutrient distributions in multi-year landfast sea ice (fast ice) in Lützow-Holm Bay, East Antarctica. Based on sea-ice salinity, oxygen isotopic ratios, and thin section analyses, we found that the multi-year fast ice grew upward due to the year-by-year accumulation of snow. Compared to ice of seawater origin, nutrient concentrations in shallow fast ice were low due to replacement by clean and fresh snow. In deeper ice of seawater origin (the lower half of the multi-year fast ice column), remineralization was dominated by the degradation of organic matter. In addition, denitrification was detected in the low brine volume fraction and impermeable multi-year ice due to their disconnection from gas and water exchanges with the atmosphere and under-ice water. By comparison with first-year ice, we develop a conceptual image of the evolution of nutrient concentrations, with biological uptake dominating in relatively young ice and remineralization dominating in older, multi-year ice under the physical process of brine drainage.