  We study the Matrix theory description of M-theory compactified on $T^4$ and
$T^5$. M-theory on $T^4$ is described by the six dimensional (2,0) fixed point
field theory compactified on a five torus, $\widetilde T^5$. For M-theory on
$T^5$ we suggest the existence of a new theory which is compactified on a
$\widetilde T^5$. The IR description of this theory is given by the (2,0)
theory with a compactified moduli space. This new theory appears to be a new
kind of a non-critical string theory. Clearly, these two descriptions differ
from the ``standard'' Super-Yang-Mills on the dual torus prescription.
