Nagara peanuts (Vigna unguiculata ssp. cylindrica) are a local plant from South Kalimantan, which are planted in swamp land. However, the cultivation of nagara beans in swamp land is still limited because they can only be planted once a year, namely during the dry season. To overcome this problem, nagara beans which have adapted to swamp land are re-adapted to dry land by paying attention to soil fertility by providing additional organic material such as water hyacinth mulch (Eichornia crassipes) and identifying the diversity of soil macrofauna. The aim of this research was to determine the diversity of soil macrofauna at each treatment of water hyacinth (Eichornia crassipes) mulch. This research used a Completely Randomized Design (CRD). The experiment consisted of three treatment levels, namely without mulch (M0), fresh water hyacinth mulch (M1) 4 kg/m2, and dry water hyacinth mulch (M2) 3 kg/m2. The results of this research show that the diversity of soil macrofauna in the three treatments has moderate index values. The individual richness of soil macrofauna in the three treatments had low index values. Soil macrofauna evenness has a value of more than 0.6, indicating that the distribution of individuals per species is even. This is in accordance with the macrofauna dominance value, that there is no dominant species.