Giant sensitive plant (Mimosa pigra L.) belongs to Fabacae family, is an invasive species containing biological compounds (allelopathic chemicals) to control other plants. This study was conducted to investigate the effect of different extraction methods on the phenolic, flavonoid, mimosinne contents and evaluation the ability to inhibit germination, growth of radish (Raphanus sativus L.) and leaf mustard (Brassica juncea) from Mimosa pigra leaf extract. The total phenolic content, flavonoid and mimosine concentrations were determined by spectrophotometric measurement, and the ability to inhibit growth was performed in a laboratory, on petri dishes in 5 days. The method of incubation for mimosa leaves in 60 minutes at a temperature of 50°C has the highest phenolic, flavonoid and mimosine concentrations of 6.63 mg, 1.86 mg and 1.89 mg. The 60-minute incubation method inhibited radish with the highest 21.44% of the root length, 38.01% of the shoot height but inhibited the lowest germination rate and dry weight. The mixture of leaf extract 10% and vinegar 0.1% inhibited completely germination, root length, shoot height, and the weight of radish and leaf mustard compared to the control. This result provides scientific literature on the potential ability of this plant to control weeds.