  Quantum coherence and non-Markovianity of an atom in dissipative cavity under
weak measurement are investigated in this work. We find that, the quantum
coherence obviously depends on the atomic initial state, the strength of the
weak measurement and its reversal, the atom-cavity coupling constant and the
non-Markovian effecct. The more obvious the weak measurement effect is, the
better the protection of coherence is. The quantum coherence is preserved more
efficiently for lager the atom-cavity coupling. The stronger the non-Markovian
effect, the more slowly the coherence reduces. This is, the quantum coherence
can be effectively protected by means of controlling these physical parameters.
