  We study the recently observed $\Omega(2012)$ baryon in QCD sum rules. We
construct the $P$-wave $\Omega$ baryon currents with a covariant derivative,
and perform spin projection to obtain the currents with total spin 1/2 and 3/2.
We then apply the parity-projected QCD sum rules to separate the contributions
of the positive and negative parity states. We extract the masses of $J^P =
1/2^-$ and $3/2^-$ states to be $M_{1/2^-} = 2.07^{+0.07}_{-0.07}{\rm~GeV}$ and
$M_{3/2^-} = 2.05^{+0.09}_{-0.10}{\rm~GeV}$. Both results are in good agreement
with the experimental result. Therefore, it is likely that the $\Omega(2012)$
is a negative parity state, which is interpreted as a $P$-wave excited state in
the quark model. However, its spin is not determined in the present analysis,
which can be done by detailed study on its decay properties.
