  A general form of a two-qubit system is obtained under the effect of Lorentz
transformation. We investigate extensively some important classes in the
context of quantum information. It is shown Lorentz transformation causes a
decay of entanglement and consequently information loses. On the other hand, it
generates entangled states between systems prepared initially in a separable
states. The partial entangled states are more robust under Lorentz
transformation than maximally entangled states. Therefore the rate of
information lose is larger for maximum entangled states compared with that for
partially entangled states.
