Phenolic compounds have been widely studied to possess diverse bioactivities which could be beneficial to human health. The germination is an efficient and economical process for improving the nutritional quality, functionality and the concentration of bioactive compounds in grains. Thus, the changes of the total phenolic content (TPC), flavonoids content (FC) (mg gallic acid equivalents/g dry weight) (GAE mg/g) and the antioxidant properties evaluated by the methods DPPH-radical scavenging and ABTS-radical scavenging (mol Trolox equivalent/g dry weight) of extracts obtained from non-germinated and germinated mustard seeds were investigated. For germination process, the seeds were placed in trays with humidified filter papers and incubated at 25°C for 48h. The recovering of bioactive compounds was performed by incubation of the samples with three different solvents: 100% water, 50:50% ethanol/water and 100% ethanol, during 1h at 25°C and 150 rpm agitation. Comparing the non-germinated and germinated samples, the use of 100% water as solvent resulted in TPC of 6.59 and 11.26 GAE mg/g and FC of 2.16 and 2.18 GAE mg/g, respectively. For antioxidant activity, the germinated samples showed an increase in DPPH-radical scavenging from 118.61 to 149.05 mol Trolox EQ/g and the ABTS-radical scavenging increased from 28.67 to 76.20 mol Trolox EQ/g. Similar results were detected for the extracts obtained using 50:50% ethanol/water, in which the ABTS-radical scavenging increased from 32.18 to 78.50 mol Trolox EQ/g and DPPH-radical scavenging showed an increase from 122.98 to 134.36 mol Trolox EQ/g after germination. It was observed that the 100% ethanolic extract did not present a significant increase (p <0.05) in TPC, whereas FC increased from 11.43 GAE/g to 18.04 GAE/g which may explain the augment in DPPH-radical scavenging (152.32 mol TE/g to 175.64 mol TE/g and ABTS-radical scavenging (1.73 mol TE/g to 2.67 mol TE/g) after germination.