  The exclusive decay of $\Upsilon$ to a vector plus pseudoscalar charmonium is
studied in perturbative QCD. The corresponding branching ratios are predicted
to be of order $10^{-6}$ for first three $\Upsilon$ resonances, and we expect
these decay modes should be discovered in the prospective high-luminosity
$e^+e^-$ facilities such as super $B$ experiment. As a manifestation of the
short-distance loop contribution, the relative phases among strong,
electromagnetic and radiative decay amplitudes can be deduced. It is
particularly interesting to find that the relative phase between strong and
electromagnetic amplitudes is nearly orthogonal. The resonance-continuum
interference effect for double charmonium production near various $\Upsilon$
resonances in $e^+e^-$ annihilation is addressed.
