A unique method of patterning YBaCuO thin films based on the inhibition of superconductivity by Si‐YBaCuO intermixing has been developed. In the experiment, a thin Si film was first evaporated on a MgO substrate and subsequently patterned using laser direct‐write etching. Multilayered YBaCuO thin films were then deposited bye‐beam evaporation and annealed in a rapid thermal annealing system for 30–90 s at 980 °C. The YBaCuO film deposited on the silicon regions became insulating. Auger depth profiling measurements indicate that Si‐YBaCuO intermixing had occurred in these areas. Between the insulating regions, narrow YBaCuO superconducting lines were formed. For both 10‐&mgr;m‐wide, 1‐mm‐long and 2.5‐&mgr;m‐wide, 80‐&mgr;m‐long lines, theTcwas observed above 76 K. The critical current density of the lines was measured to be 300 A/cm2at 75 K. This patterning technique may be useful for fabrication of highTcsuperconducting interconnects and devices.