The Interstellar Medium (ISM) represents a small fraction of the Milky Way matter, but it plays a fundamental role because it governs the galactic evolution and its structure.Most of the ISM gaseous constituents have been identified through their emission or absorption characteristics, however, the "diffuse interstellar bands" (or DIBs), still has no counterpart in absorbing species.A favourable situation is the presence of a DIB (with central wavelength 862 nm) within the spectral interval of the Radial Velocity Spectrometer (RVS), one of the instruments of the ESA Gaia mission. The first part of the work presented in this document is directly related to the construction of this future catalog and its potential use.I have developed a profile fitting code adapted to the emph{Gaia} DIB and to the RVS instrument. I estime in my thesis how many DIBs will be measured.The second part of this thesis is related to the three-dimensional (3D) mapping of the ISM. I made the first tomography based on composite data, both extinctions and DIBs and showed this is a viable way. I ran parallel inversions of two extinction and DIB datasets for the same target stars and compared the distributions.The full 3D tomographic inversion technique in this case requires an unrealistically large computing time. I have developed a technique and I have applied it to a new catalog of 30 millions of extinction measurements based on Gaia.Finally, I used ground-based stellar spectra to extracted radial velocities and columns of IS absorbing species and participated to the first step of a "kinematic" 3D map of the ISM.