ABSTRACT Traffic is increasing day by day due to increased vehicle ownership and infrastructure development. As the modern highway transportation has high speed, high traffic density, heavy load and channelized traffic, bituminous concrete is subjected to various types of distress such as rutting, fatigue cracking and raveling. Fatigue cracking occurs because bituminous layers are weak in tension. Therefore reinforcement of the bituminous mixes is one approach to improve tensile strength. Natural fibers can be used for reinforcing as a substitute for synthetic fibers due to their lower cost, ecological recycling and low specific gravity. Among natural fibers growing attention is being paid to coir fiber due to its easy availability, good wearing resistance and more durable property. Also rutting along wheel path causes vehicle hydroplaning during rainy seasons due to loss of skid resistance. As well as water accumulated over the longitudinal depressions damages bond between binder and aggregates. Therefore there is a need for a durable mix which can increase the service life of pavement thus reduces life cycle cost. This study is about use of coir fiber in pavement construction to improve the performance characteristics of the asphalt mixture being used. Stone matrix asphalt mixture is a rut resistant and durable mix which is reinforced with coir fiber and tested for various performance characteristics. Coir fiber is a sustainable material which can be used for rutting resistant mixture.   Keywords: Stone matrix asphalt, Coir fiber, rutting