  We study the coupling of two longitudinal Z-bosons to two gluons via
technicolor interactions. Noticing a similarity of this process to $2 \gamma
\rightarrow 2 \pi^{0}$, we calculate the amplitude in chiral perturbation
theory in one-generation technicolor model. At the invariant mass of $
Z_{L}Z_{L}$ above the colored pseudo-Goldstone boson threshold, we find the
signal in proton collisions at $\sqrt{s} = 14\, TeV$ is stronger than the
standard model background by an order of magnitude, and is large enough to be
easily observable at LHC.
  The cross section for $W_{L}^{+}W_{L}^{-}$ pair production is also presented.
