Two measurements of the lifetime of neutral and charged B
mesons in ppbar collisions at sqrt s = 1.8 TeV by the CDF experiment
are presented.  The first relies on the study of exclusive decays of
the type B -> psi K, the second on semileptonic decays of a B meson into a D^*
or a D.  The combined results are tau(B^+) = 1.62 +/- 0.09 ps, tau(B^0) =
1.60 +/- 0.09 ps and tau(B^+)/tau(B^0) = 1.00 +/- 0.07.