The current density of Ti‐56mass%Ni (Ti‐50at.%) alloy after abrasion in simulated bioliquids was measured using a potentiostat to estimate the amount of metallic ions released from the alloy during repassivation and maturation. The current density in saline, saline with and without N
$_{2}$
bubbling, and Hanks’ solutions with and without proteins after abrasion was measured and the amount of released ion was calculated from the integrated current density with time, assuming that Ti
$^{4+}$
and Ni
$^{2+}$
are equivalently released. No difference in the amount of released ion was observed between saline with and without N
$_{2}$
bubbling. Also, no difference was observed between saline and pH 7.4 Hanks’ solution. More Ti
$^{4+}$
and Ni
$^{2+}$
were released in bioliquids with proteins than in saline with and without N
$_{2}$
bubbling (
$p<{}$
0.05). That is, dissolved oxygen and inorganic ions in Hanks’ solution did not influence the amount of released ion, but proteins influenced it. The release of metallic ions from metals and alloys in biological systems can be estimated by the methodology employed in this study.
