Technical Abstract: Isolation of high quality peanut RNA and DNA is a prerequisite for transcript analyses and genetic studies. The presence of phenolic compounds and polysaccharides in peanut tissue can decrease yield quantity and quality which may render the isolated nucleic acid products unsuitable for various molecular studies. A method was developed to isolate both high quality RNA and DNA from the same peanut leaf or root tissue. This method utilizes guanidium salt as a strong denaturant in the extraction buffer and phenol-chloroform extraction, followed by LiCl precipitation to separate DNA from RNA. Spectrophometric analysis showed 260/230 ratios above 2.0 indicating no contamination from phenolics and polysaccharides. RNA was shown to be suitable for RT-PCR based on Actin primer amplification and DNA was suitable for enzyme digestion and PCR amplification. This result shows that RNA and DNA isolated using this method can be appropriate for molecular studies in peanut.