Properties of differently doped Zn0.95Cd0.05Te〈110〉 crystals as terahertz (THz) wave emitter are studied using THz time-domain spectroscopy. It is observed that the THz generation efficiency increases as the DC resistivity increases when the resistivity of crystals is greater than 102 Ω·cm, but the efficiency saturates and even declines when the resistivity goes beyond 106 Ω·cm. It is revealed that the dispersion properties of crystals play an important role, besides the doping-dependent absorption in THz region.