  We calculate the contribution of anomalous top-quark interaction with a
gluon, photon, and $Z$-boson (FCNC) to $t \bar t$ pair production in hadronic
collisions. Using the current data from Run~1 of the Tevatron we evaluate the
upper limit on the the anomalous coupling of $t$-quark with gluon,
$|\kappa_g/\Lambda| \le 0.52$ TeV$^{-1}$. We examine the production of double
top ($t t$ or $\bar t \bar t$) at hadronic colliders as a result of FCNC
interactions of the top quark. It is shown that the study of such reactions at
LHC collider makes possible to obtain the constraint on strength of coupling at
the level of $|\kappa_g /\Lambda| \le 0.09$ TeV$^{-1}$.
