Abstract: Decomposition of organic waste in cropland led to production of contaminated liquid named (leachate) that has toxic and hazardous compositions, so it is considered a significant threat for the environment. In this study, Nutrient Film Technique (NFT) with filtered date-palm wastes as an adsorbent for the purification of compost leachate was investigated. In order to be consistent, waste of palm trees were chopped using a special combine, then classified by using a sieve in three sizes 0-0.5, 0.5-1 and 1-2 cm. In each treatment, 30 L of leachate flowed for 72 h in the current system and at the start of the experiment (leachate input) as a control and then at 12, 24, 48 and 72 h after the initial testing, samples of circulating leachate in the system, were taken and parameters Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD), Total Soluble Solids (TSS) and concentration of heavy metals (Zn, Cu and Fe) were measured. After 72 h and the last sampling of the first treatment, the system completely emptied and washed. The same procedures were performed in the other treatments. Results showed the highest reduction in BOD5, COD, TSS in the NFT system for palm wastes in 1-2 cm size, after 72 h. The highest reduction of heavy metals of leachate was also obtained in 1-2 cm size. So it could be an inexpensive method that can be replaced to other forms of methods of leachate treatment in Iran and the world.