In the context of the left-right twin Higgs (LRTH) model, we first examine the effects on the Ztt production at the ILC and LHC. Our results show that the cross-sections can be significantly deviated from the standard model predictions and thus provide a good probe for the LRTH model. We also estimate the new production channel, ZtT or ZtT production, at the LHC. Compared with Ztt production, we find that the ZtT production can have a sizable production rate when the scale f is not too high. Considering the dominant decay mode T ->phi(+) b -> tbb, we find that ZtT final state has less background than Ztt production and may likely be observable at the LHC. Copyright (c) EPLA, 2014