Root competition is one of the main sources of interference in rubber based intercropping systems. This needed investigation and the growth and distribution of roots were studied in an intercropping system where rubber was planted in east-west oriented rows and in contours and coffee, cinnamon and grass were planted in the inter-row. Root length density (RLD) of rubber of the intercrops in the inter-row was studied over a period of 7 years. RLD in between two rubber in a row was high initially. Whole of the inter-row was gradually invaded by the rubber roots by the end of the 6th year in both planting systems and were not reduced due to the presence of intercrops. Cinnamon as the intercrop however has favoured the growth of rubber roots. Intercrop root length densities declined with time and was reduced to low levels by the end of the 7th year. This decline was severe and rapid in case of grass that had a very high density initially. Cinnamon had low RLD through out and the decline was not high as observed for Grass or Coffee.