The quantum correlation of a two-qubit Heisenberg XXZ model was investigated through applying two independent and controllable magnetic fields (B+b) and (B－b) on the two qubits respectively and changing the coupling parameter Jz, magnetic field B, inhomogeneous magnetic field b and temperature kT. The behavior of quantum correlation and that of thermal entanglement under one and the same parameter is compared. The results show that quantum correlation can exist for a wider parameter range than thermal entanglement. In addition, for a certain region of parameter, quantum correlation and thermal entanglement exhibit completely different behaviors.