Abstract: Determination of bed-sediment quality and macrobenthos abundant were carried out in Labu River System and two selected sites in Langat River. The study area is situated in Langat Basin which has a total area of 2938 km2 . Identification and quantitative analysis revealed that only macrobenthos from the family of Tubificidae was dominating along the rivers. Tubificidae was strong correlated (r=0.97) with sediment grain size 125-63 μm compared to 63-38 μm (r=0.90) and < 38 μm (r=0.81). High correlation (r=0.82) was observed between Tubificidae abundant and organic content in the bed-sediments. Labu River System and selected sites in Langat River were polluted with organic constituent for a long period of time based on quantity of Tubificidae acquired.