This study aims to determine the effect of various doses of apu wood green manure (Pistia stratiotes L.) on mustard greens (Brassica juncea L.) and determine the best dose of green mustard green manure on mustard greens. This research was carried out at theexperimental garden, Faculty of Agriculture, University of Lambung Mangkurat from March to Mei 2021. This study used a single factor Randomized Block Design (RAK) namely various doses of apu wood green manure P0: Control (without treatment), P1: 5 tons /ha-1 (500 g/plot-1), P2: 10 tons/ha-1 (1,000 g/plot-1), P3: 15 tons/ha-1 (1,500 g/plot-1), P4: 20 tons /ha-1 (2,000 g/plot-1) there were 4 repetitions with a total of 20 experimental units. The benchmarks for observations were the number of leaves, plant height, leaf width, plant wet weight, and plant dry weight. The results showed that the green manure of apu wood had no significant effect on the parameters of leaf number, plant height, leaf width, plant wet weight, and plant dry weight observed for 28 DAP so it was not followed up with DMRT test with a level of 5%.