Purun danau (Lepironia articulata Retz) is a non-timber forest product that can live in peat swamps with high acidity. Besides being able to be utilized as a biofilter to improve water quality, purun is also used by the people of Purun Village as a basic material for making various products. Based on these benefits, a study was conducted to analyze the plants found and their associations as well as the potential that can be developed and maintained from purun danau. The selection of research locations was based on a purposive method and sampling using association sampling plots and interviews were conducted to obtain supporting data. Data taken in the field included the potential and plants found in the observation plot, pH and peat depth which were finally analyzed using a 2x2 contingency table and tested using the Ochiai Index (IO) calculation. The results showed that purun danau (Lepironia articulata Retz) was associated with 9 other plant species, namely a very high association between purun danau and purun tikus and a low scale between purun danau and cinnamon. The potential of purun danau in 1 ha of land can produce 11 tons of wet weight and only get 4.4 tons of dry weight.