  In this brief report, the microcausility of quantum field theory on
spin-induced noncom- mutative spacetime is discussed. It is found that for
spacelike seperation the microcausality is not obeyed by the theory generally.
It means that Lorentz covariance can not guaran- tee microcausality in quantum
field thoery. We also give some comments about quantum field thoeries on such
noncommutative spacetime and the relations between noncommutative spacetime and
causality.

High Energy Physics - Theory