The interaction between a single and a double strand poly-A and single wall carbon nanotubes is studied with SEIRA, SERS, and AFM techniques. After the purification and separation, the sample of nanotube-poly-A contains 1-5 nanotubes covered by poly-A. According to SEIRA and SERS spectroscopy, poly-A in a single strand form preserves its initial conformation with numerous disorders and breaks in a single strand of poly-A at the carbon nanotube surface. After the adsorption on the nanotube surface, the double strand form of poly-A changes its conformation with a partial loss of the pairing between adenine bases. The main cites of the interaction of poly-A with nanotubes are adenine and phosphate groups.