BACKGROUND:: Currently, there are many methods to extract cartilage RNA reported in the literature, and classic Trizol method has been mostly reported in China. However, it is discovered that RNA extracted by the Trizol method cannot meet the needs of the follow-up experiments. OBJECTIVE:: To explore the difference of different methods to extract total RNA from the cartilage tissues of Sprague-Dawley rats. METHODS:: Nine Sprague-Dawley rats of 3 months old were selected to extract total RNA respectively by Rneasy Lipid Tissue Kit, RNAout kit and classic Trizol method. Agarose gel electrophoresis was used to detect RNA integrity in order to explore the best extraction scheme of total RNA. RESULTS AND CONCLUSION:: When Trizol method was used to extract RNA, the A260/A280 value was 1.58, indicating that the purity was not high. Due to a large number of proteoglycan and collagen in the cartilage, RNA extracted using RNAout method cannot meet the needs of the follow-up study. When RNeasy® Mini Kit and liver method (Trizol) were used to extract RNA, the A260/A280 values were 2.00 and 1.98, respectively, indicating that the extracted total RNA or nucleic acid had high purity. The RNA electrophoresis results showed that using RNeasy ®Mini Kit, RNAout and liver method (Trizol), 18 s, 28 s and 5 s stripes were visible; but there was no stripe using Trizol method. For RNAout method, 28 s and 18 s stripes were unclear. These results show that the total RNA obtained by the Rneasy Lipid Tissue Kit has the high purity, integrity and stability, and can successfully synthesize double-stranded cDNA by reverse transcriptase, but RNAout kit and classic Trizol methods cannot meet the need of subsequent experiments. SUBJECT HEADINGS:: cartilage; RNA; rats FUNDING:: the National Natural Science Foundation of China, No. 81173285