  Black hole (BH) production at colliders is possible when the colliding energy
is above the Planck scale, which can effectively be at TeV scale in models of
large extra dimensions. In this work, we study the production of black holes at
colliders and discuss the possible signatures. We point out the ``$ij\to {\rm
BH}+ $ others'' subprocesses, in which the BH and other SM particles are
produced with a large transverse momentum. When the BH decays, it gives a
signature that consists of particles of high multiplicity in a boosted
spherical shape on one side of the event and a few number of high $p_T$ partons
on the other side, which provide very useful tags for the event.
