  The standard hybrid Monte Carlo algorithm uses the second order integrator at
the molecular dynamics step. This choice of the integrator is not always the
best. Using the Wilson fermion action, we study the performance of the hybrid
Monte Carlo algorithm for lattice QCD with higher order integrators in both
zero and finite temperature phases and find that in the finite temperature
phase the performance of the algorithm can be raised by use of the 4th order
integrator.
