  We summarize the current top quark mass ($m_t$) measurements from the CDF and
D0 experiments at Fermilab. We combine published results from Run I
(1992--1996) with the most precise published and preliminary Run II
(2001--2011) measurements based on $p\bar{p}$ data corresponding to up to
$9.7\:{\rm fb}^{-1}$ of $p\bar{p}$ collisions. Taking correlations of
uncertainties into account, and combining the statistical and systematic
contributions in quadrature, the preliminary Tevatron average mass value for
the top quark is $m_t = 174.30 \ \pm 0.65\:\mathrm{GeV}/c^{2}$, corresponding
to a relative precision of $0.37\%$
