  Motivated by the recent precision measurements of the W boson mass and top
quark mass, we test the Littlest Higgs model by confronting the prediction of
M_W with the current and prospective measurements of M_W and M_t as well as
through the correlation among M_W, M_t and Higgs mass. We argue that the
current values and accuracy of M_W and M_t measurements tend to favor the
Littlest Higgs model over the standard model, although the most recent
electroweak data may appear to be consistent with the standard model
prediction. In this analysis, the upper bound on the global SU(5) symmetry
breaking scale turned out to be 26.3 TeV. We also discuss how the masses of the
heavy gauge boson M_B in the Littlest Higgs model can be predicted from the
constraints on the model parameters.
