In this paper, we applied the potentiostatic anodisation method on the new Ti–20Nb–10Zr–5Ta alloy surface with the aim to increase its stability and bioactivity. The morphology (SEM) and composition (Raman, FT-IR) of the obtained anodisation nanolayer are studied. Also, electrochemical stability (by cyclic potentiodynamic polarisation and EIS), corrosion resistance (by linear polarisation), long-term behaviour (by monitoring of the open circuit potentials and corresponding open circuit potential gradients) and the characterisation of the layers deposited on the alloy surface after 1000 h in acid, neutral and alkaline Ringer and neutral Ringer–Brown solutions are presented. By potentiostatic anodisation, on the alloy surface was electrodeposited a continuous nanolayer containing TiO2 rutile type oxide. The anodised layer possesses better protective properties and at the same time better porosity, therefore a higher stability and bioactivity in comparison with the native passive film. After 1000 h in the testing solutions promoted the deposition of the brushite, phosphatotitanate and hydroxyapatite, precursors, respectively component of the human bone, namely this layer is bioactive.