Thick film thermosensor is firstly fabricated on 96% Al2O3 ceramic substrate successfully by laser micro-cladding thick film paste. The sensors have excellent definition and narrow width (minimum 60 μm) with TCR 2.33×10-3 /℃, time answering time 2.3 s and linearity tolerance <1 ℃. The processing parameters that affects the fabricated sensor performance are studied. The performances about the sensors fabricated by the laser micro-cladding technique are characterized. The experimental results demonstrate that the thermosensors fabricated by laser micro-cladding have excellent performances, which are a little better than those fabricated by the traditional silk screen printing methods.