Master degree ThesisStars form from the gravitational collapse of massive clouds of gas and dust in the interstellar medium. Although massive stars play an important role in determining the evolution of galaxies, our understanding of their formation is still relatively poor. Molecular clouds can be observed through the dust thermal continuum emission and the line emission of molecules. In this work we present a multi-wavelength study of the compact structures in the Cygnus X region. We have combined data from the Balloonborne Large Aperture Submillimeter Telescope (BLAST), with archival data from millimeter to mid-infrared wavelengths. We have thus constrained the spectral energy distribution of 184 high-mass young objects found by BLAST and estimated their physical properties, finding that these sources are in various evolutionary phases. We have also identified the most likely candidates of high-mass starless cores, which represent the earliest stages of high-mass star formation.