  We study the azimuthal asymmetry of the unpolarized Drell-Yan in the
framework of the T-odd functions. We find, on the basis of quite general
arguments, that for |{\bf q}_{\perp}| << Q such an asymmetry decreases as
Q^{-2}, where {\bf q}_{\perp} and Q are respectively the transverse momentum
and the center-of-mass energy of the muon pair. The experimental results
support this conclusion.
