Chemical evolution of r-process elements in the Milky Way disc is still a matter of debate. In the context of the Gaia mission, one needs robust and numerous chemical abundances of r-process elements complementary to this all sky survey. We took advantage of high resolution HARPS spectra from the ESO archive in order to derive precise chemical abundances of 3 r-process elements Eu, Dy & Gd for a sample of 4355 FGK Milky Way stars. The chemical analysis has been performed thanks to the automatic optimization pipeline GAUGUIN. Based on the [α/Fe] ratio, we chemically characterized the thin and the thick discs, and present, in this poster, results of these 3 r-process element abundances in both discs, tracing and discussing for the first time their evolution as a function of the metallicity and alpha-enrichement, used as an age proxy.