Abstract: To investigate the behavior of sisal fibre and waste plastic modified asphalt concrete mixes, a study was done to determine the feasibility of modifying the behaviour of open graded asphalt (OGA) concrete mix through the use of sisal fiber and waste plastics. The main objective of this research was to analyze and study how sisal fibre and waste plastics can be used to reduce bitumen drain down and effectively utilize waste plastics in construction of flexible pavement to improve on strength.