An efficient and economic method for high quality RNA preparation from plant tissues was established. To avoid RNA degradation, sucrose, potassium chloride and Mg²⁺ were included in the extraction buffer. Plant tissues were lysed in the extraction buffer, then ribonucleases (RNAses) and other proteins were denatured and extracted by phenol/chloroform. After that, the DNA was selectively fractionated from RNA with sodium acetate (NaAc) (pH 5.6). The isolated RNA with this method gave good yield. Results of non-denaturing electrophoresis or formaldehyde agarose gel electrophoresis both showed higher amount of 25 S ribosomal RNA (rRNA) than that of 18 S rRNA. Northern hybridization gave sharp and clear signals. Both plastid gene and nuclear gene were amplified successfully by RT-PCR. These results show that, the RNAs isolated with this method are in good integrity and purity, and can meet the needs of most molecular biological experiments including gene cloning and expression analysis. In this method, phenol/chloroform were used to remove proteins and inactivate RNAses, NaAc (pH 5.6) was used to precipitate RNAs, thus largely reduced the experimental expenses.