RESUMEN

In the present talk we make a resume of the steps to measure the lifetime of the Bs meson in hadronic mode J/psi(muon+ muon- ) Ph(Pion+ Pion- )at D0. D0 experiment is localized at TEVATRON in Fermilab USA, we will describe the cuts, the model and the calculation of the systematics errors . This results is the best in the world in a fully reconstructed mode. For a crosscheck we also measure the lifetime of the Bd meson in the hadronic mode J/Psi(muon) K*(K+ Pion-), these mode is topological similar to Bs. These analysis was published in PRL Phys. Rev. Lett. {94}, 042001 (2005) hep-ex/0409043.