This study is aimed to evaluate the antioxidant and antibacterial activities of two plants collected in Kien Giang province, Vietnam. The antioxidant property was determined for their antioxidant activity by DPPH, ABTS+, RP và TAA methods in vitro. The results showed that the ethanolic leaves extract of Mimosa pigra displayed in vitro antioxidant activities with the IC50 (effective concentration) values are 67.12 µg/mL, 39.22µg/mL, 32.16 µg/mL and 71.86 µg/mL respectively. Similarly, the ethanolic leaves extract of Senna alata with IC50 values are 357.19 µg/mL; 40.39 µg/mL; 331.03 µg/mL and 119.59 µg/mL respectively. Total phenolic and total flavonoid of leaf extract of Senna alata contents were 203.57 mg GAE/g and 46.31 mg QE/g, respectively. Similarly, total phenolic and total flavonoid of leaf extract of M. pigra contents were 306.08 mg GAE/g and 38.71 mg QE/g respectively. The antibacterial activity is investigated in 4 bacterial strains which can cause aquatic diseases. The results proved that the ethanol extract of M. pigra had high efficiency in antimicrobial activity
on four bacterial strains Aeromonas dhakensis, Aeromonas hydrophilaEdwardsiella ictaluri, Streptococcus agalactiae. These findings indicated that M. pigra is a very potential herb containing natural antioxidant and antibacterial compounds.