Abstract: Eu-doped ZnO nanorods were synthesized by hydrothermal method, and the effect of Eu doping concentration on the structures, morphologies and optical properties of the samples were mainly researched. The results showed that the Eu ions were successfully doped into the ZnO, and the samples were composed of nanorods with diameter of 15-25 nm. The crystallization quality of the samples was worse with increasing the Eu doping concentration due to the more defects, and the red emission of Eu3+ was enhanced with Eu doping. In addition, the UV emission had a red shift due to the additional impurity level of Eu.