The paint adhesion on typical thermoplastics like PPS or PAEK is poor due to their hydrophobic character. A reliable surface pre-treatment is necessary to clean the surface without any material deterioration or fibre release. For this purpose, a commercial 30 W KrF excimer laser with a wavelength of 248 nm and a pulse duration of 25 ns was used. Experimental results for this promissing surface pre-treatment technology will be presented and discussed.