  We report on measurements of the mass and total decay width of the W boson
with the L3 detector at LEP. W-pair events produced in $\mathrm{e^+e^-}$
interactions between 161 GeV and 183 GeV centre-of-mass energy are selected in
a data sample corresponding to a total luminosity of 76.7 pb$^{-1}$. Combining
all final states in W-pair production, the mass and total decay width of the W
boson are determined to be $\mathrm{M_W}=80.61\pm0.15$ GeV and
$\Gamma_{\mathrm{W}}=1.97\pm0.38$ GeV, respectively.
