  I review the current status of lattice calculations of light and heavy quark
masses. Significant progresses, in these studies, have been allowed by the
introduction of improved actions and non-perturbative renormalization
techniques. Current determinations of light quark masses are accurate at the
level of 20%, where the main source of uncertainty is represented by the
quenching error. The determination of the bottom quark mass is accurate at the
impressive level of 2%. As final averages of lattice results, I quote mud(2
GeV) = (4.5 +- 1.0) MeV, ms(2 GeV) = (110 +- 25) MeV and mb(mb) = (4.26 +-
0.09) GeV.
