Résumé : A measurement of the mass of the Higgs boson in the diphoton decay channel is presented. This analysis is based on 35.9 of proton-proton collision data collected during the 2016 LHC running period, with the CMS detector at a centre-of-mass energy of 13 TeV. A refined detector calibration and new analysis techniques have been used to improve the precision of this measurement. The Higgs boson mass is measured to be . This is combined with a measurement of already performed in the decay channel using the same data set, giving . This result, when further combined with an earlier measurement of using data collected in 2011 and 2012 with the CMS detector, gives a value for the Higgs boson mass of . This is currently the most precise measurement of the mass of the Higgs boson.