  Preliminary results on the measurement of the top quark mass (mt) at the
Tevatron Collider are presented. In the dilepton decay channel, the CDF
Collaboration measures mt=175.0(+17.4)(-16.9)(stat.)+/-8.4(syst.) GeV/c2, using
a sample of ~126 pb-1 of proton-antiproton collision data at sqrt(s)=1.96 TeV
(Run II). In the lepton plus jets channel, the CDF Collaboration measures
177.5(+12.7)(-9.4)(stat.)+/-7.1(syst.) GeV/c2, using a sample of ~102 pb-1 at
sqrt(s)=1.96 TeV. The D0 Collaboration has newly applied a likelihood technique
to improve the analysis of ~125 pb-1 of proton-antiproton collisions at
sqrt(s)=1.8 TeV (Run I), with the result: mt=180.1+/-3.6(stat.)+/-3.9(syst.)
GeV/c2. The latter is combined with all the measurements based on the data
collected in Run I to yield the most recent and comprehensive experimental
determination of the top quark mass: mt=178.0+/-2.7(stat.)+/-3.3(syst.) GeV/c2
