Polyurethane (PU) is one of the most common polymer material used in day today life due to its outstanding features like light weight, cheap in cost, and remarkable sound insulation. PU is extensively used in acoustic and insulation applications because of its porous characteristics. But one of the disadvantages of using foam as the acoustic material is emission of the volatile organic compounds in indoor environments, non-biodegradability and landfill issues. To overcome this important environmental issue of the petrochemical based sound absorbing porous materials it is essential to developing green, cost-effective, efficient and bio degradable porous materials for sound absorption. This paper presents investigations on the acoustical properties of castor oil polyol based kenaf fibre reinforced thermoplastic bio-composites and concepts for highly absorbent material. The results show that castor oil based kenaffibre sample shows good acoustic properties at high frequencies and can be used as an alternative replacement to conventional synthetic fiber interior products. © 2018 Elsevier Ltd.