Spermine inhibitits several non-selective TRP cation channels and N-type Ca²⁺-channels. In erythrocytes, spermine-concentration decreases gradually with aging, which is paralleled by increase of cytosolic Ca²⁺-concentration. Cytosolic Ca²⁺ in turn triggers suicidal erythrocyte death or eryptosis, characterized by cell shrinkage and membrane scrambling. The present study explored the influence of spermine on erythrocyte cation channels and eryptosis. Cytosolic Ca²⁺ was estimated from Fluo-3 fluorescence, cell volume from forward scatter, cell membrane scrambling from annexin V binding, and cation channel activity with whole cell patch-clamp in human erythrocytes. As a result, 200mM spermine blunted the increase of intracellular Ca²⁺, cell shrinkage and annexin V binding following 48 hours exposure of the cells at +37°C. In contrast, short exposure (10–30 min) of the cells to 2 mM spermine rather increased cytosolic Ca²⁺ and annexin binding. Intracellular addition of spermine at sub-physiological concentrations (0.2mM) significantly decreased the conductance of monovalent cations (Na⁺,K⁺,NMDG⁺) and of Ca²⁺ in whole-cell patch clamp experiments. Moreover, spermine (0.2mM) blunted the stimulation of voltage-independent cation channels by Cl^- removal. Spermine (0.2mM and 200mM) added to the extracellular bath solution similarly inhibited the cation conductance in Cl^--containing bath solution. The effect of 0.2mM spermine, but not the effect of 200mM was rapidly reversible. Acute addition (250mM) of a naphthyl acetyl derivative of spermine (NASPM, 200mM), again significantly decreased basal cation conductance in NaCl bath solution and inhibited voltage-independent cation channels. In conclusion, spermine is a powerful regulator of erythrocyte cation channels, cytosolic Ca²⁺ activity and thus cell survival.