  In a recent work (hep-th/9905198) we argued that a certain matrix quantum
mechanics may describe 't Hooft's monopoles which emerge in QCD when the theory
is projected to its maximal Abelian subgroup. In this note we find further
evidence which supports this interpretation. We study the theory with a
non-zero theta-term. In this case, 't Hooft's QCD monopoles become dyons since
they acquire electric charges due to the Witten effect. We calculate a
potential between a dyon and an anti-dyon in the matrix quantum mechanics, and
find that the attractive force between them grows as the theta angle increases.
