A measurement of the mass of the W boson is presented which is based on a sample of 5982 −→Weν decays observed in p¯p collisions at √s=1.8 TeV with the D∅ detector during the 1992–1993 run. From a fit to the transverse mass spectrum, combined with measurements of the Z boson mass, the W boson mass is measured to be MW=80.350±0.140(stat)±0.165(syst)±0.160(scale)GeV/c2. Detailed discussions of the determination of the absolute energy scale, the measured efficiencies, and all systematic uncertainties are presented.Received 15 October 1997DOI:https://doi.org/10.1103/PhysRevD.58.012002©1998 American Physical Society