Abstract:The two methods for extracting high quality total RNA from the leaves of Citrus reticulata Banco were compared by using RNAplant Reagent (Beijing Tiangen Corporation) and RNAiso Reagent (Japanese TaKaRa Corporation), respectively. The results showed that two bands of 28S and 18S rRNA were distincted by agarose gel electrophoresis with RNAiso Reagent, which the values of A 260/A280 and A260/A230 were 1.820 and 2.088, respectively, and the yield reached 2.840 μg μl-1. At the same time, a citrus house keeping gene β-actin fragment, the 228 bp sequence was successfully cloned by RT-PCR. Otherwise, with RNAplant Reagent, the two RNA bands of 28S and 18S were dim, and the values of A260/A280 and A 260/A230 were 1.464 and 1.603, respectively, the yield of RNA was only 2.020 μg μl-1, which was lower than the standard. Therefore, the RNAiso Reagent was a better method for extracting RNA of Citrus in purity and quality, it could accord with the requirements of subsequent molecular biology reaction, such as Northern hybridization, cDNA libhrary construction and RT-PCR.