  We investigate the entropy bound for local quantum field theory in this
paper. Both the bosonic and fermionic fields confined to an asymptotically flat
spacetime are examined. By imposing the non-gravitational collapse condition,
we find both of them are limited by the same entropy bound $A^{3/4}$, where $A$
is the boundary area of the region where the quantum fields are contained in.
The gap between this entropy bound and the holographic entropy has been
verified.
