Surface planarization and masked ion-beam structuring (MIBS) of high-T c superconducting (HTS) YBa 2 Cu 3 O 7-δ (YBCO) thin films grown by pulsed-laser deposition (PLD) method is reported. Chemical–mechanical polishing, plasma etching, and oxygen annealing of YBCO films strongly reduce the particulate density (~10 –2 ×) and surface roughness (~10 –1 ×) of as-grown PLD layers. The resistivity, critical temperature T c ≈90K and critical current density J c (77K)>1 MA/cm 2 of films are not deteriorated by the planarization procedure. The YBCO films are modified and patterned by irradiation with He + ions of 75keV energy. Superconducting tracks patterned by MIBS without removal of HTS material and, for comparison, by wet-chemical etching show same T c and J c (T) values. Different micro- and nano-patterns are produced in parallel on planarized films. The size of irradiated pattern depends on the mask employed for beam shaping and features smaller than 70nm are achieved.