Persistent photoconductivity (PPC) in Cd0.7Zn0.3Se mixed crystals is investigated. We report here the first experimental observation of PPC in Cd0.7Zn0.3Se at room temperature. In the temperature region 70 K < T < 200 K, were found that the decay of PPC follows streched-exponential behavior. PPC is not observable at temperatures below 70 K, in contrast to previously reported results on most materials which exhibits dominant PPC effects at low temperatures. Experimental results show strong evidence that random local potential fluctuations induced by composition fluctuations are the origin of PPC observed here.