Objective:To evaluate all parts of Protium serratum(Wall,ex Colebr.) Engl.(P.serratum) for their phytochemistry and biological activities including antityrosinase,antioxidant,and brine shrimp lethality.Methods:Nine ethanolic extracts from different P.serratum parts such as twig,whole fruit,pericarp,and root were investigated for their phytochemical screening and biological activities in terms of tyrosinase inhibition,antioxidant against 1,1-diphenyl-2-picrylhydrazyl and hydroxyl radicals,and lethality to brine shrimp larvae.Results:Phytochemical screening also revealed the presence of flavonoids,condensed tannins,alkaloids,triterpenoids,steroids,and sugars in P.serratum.The root extract was the most effective for antityrosinase activity with IC_(50) of(21.63 ± 0.31) μg/mL,and the leaf extract exhibited the highest antioxidation activity using l,l-diphenyl-2-picrylhydrazyl and hydroxyl radical scavenging methods,with IC_(50) of(4.34 ± 0.09) and(119.80 ± 1.01) μg/mL,respectively.The essential oil extracted from the whole fruit displayed the highest toxicity against brine shrimp,with LC_(50) of(3.57 ± 1.82) μg/mL.Conclusions:This study indicates that ethanolic extracts from each P.serratum part have differences in phytochemistry and biological activities(antityrosinase,antioxidant,and brine shrimp lethality).Some parts of the plant should be considered in the further study. Objective: To evaluate all parts of Protium serratum (Wall, ex Colebr.) Engl. (P.serratum) for their phytochemistry and biological activities including antityrosinase, antioxidant, and brine shrimp lethality. Methods: Nine ethanolic extracts from different P.serratum parts such as twig, whole fruit, pericarp, and root were investigated for their phytochemical screening and biological activities in terms of tyrosinase inhibition, antioxidant against 1,1-diphenyl-2-picrylhydrazyl and hydroxyl radicals, and lethality to brine shrimp larvae. Results: Phytochemical screening also revealed the presence of flavonoids, condensed tannins, alkaloids, triterpenoids, steroids, and sugars in P. soratum. The root extract was the most effective for antityrosinase activity with IC 50 (21.63 ± 0.31) μg / mL, and the leaf extract exhibited the highest activity of using l, l-diphenyl-2-picrylhydrazyl and hydroxyl radical scavenging methods, with IC 50 (4.34 ± 0.09) and (119.80 ± 1.01) μg / mL, respectively. essential oil extracted from the whole fruit displayed the highest toxicity against brine shrimp, with LC 50 (3.57 ± 1.82) μg / mL. Conclusions: This study indicates that the ethanolic extracts from each P. serratum part have differences in phytochemistry and biological activities (antityrosinase, antioxidant, and brine shrimp lethality) .Some parts of the plant should be considered in the further study.