Abstract: In order to reveal the rules of nutrient elements and to supply scientific basic for making a suitable managing methods and improving the productivity of an agroforestry system f coconut interplanted pineapple, the processes of uptake, retention and return of the nutrient elements (N, P and K) in a five_year_old plantation of coconut interplanted pineapple located in the Rian Province, Sumatra island which run by P. T. Pulau Sambu Group (Indonesia) were studied. The results obtained show that the total annual uptake of three elements was 970.195 kg·hm－2 with the retention of 559.471 kg·hm－2 and the return of 410.745 kg·hm－2. The average cycling rate of the three nutrient elements was 42.32%, which was 27.53% greater than that in pure coconut stands. Coconut interplanted with pineapple was proved to be one of optimum cultivation patterns with higher biomass productivity and effective uses of environment resources in tropical areas.