<jats:title>Abstract</jats:title><jats:p>The 1,1‐diphenyl‐2‐picrydydrazyl (DPPH) assay on the extract of <jats:italic>Phyllanthus urinaria</jats:italic> L. (Euphorbiaceae) displayed considerable radical‐scavenging activity (<jats:italic>SC</jats:italic><jats:sub>50</jats:sub>=14.3 μg/ml). Further bioassay‐guided purification of the extract led to the isolation of a series of 15 phenolic compounds, including the ellagitannins <jats:bold>1</jats:bold>–<jats:bold>7</jats:bold>, the flavonoids <jats:bold>8</jats:bold>–<jats:bold>10</jats:bold>, and the simple hydroxylated (or glycosylated) aromatic acids <jats:bold>11</jats:bold>–<jats:bold>15</jats:bold>. Their structures were identified by spectroscopic analyses and comparison with authentic samples or literature data. The structure of repandinin B (<jats:bold>1</jats:bold>) was for the first time fully assigned by 1D‐ and 2D‐NMR experiments. The phenolic compounds <jats:bold>1, 3, 4, 6, 9, 11</jats:bold>, and <jats:bold>15</jats:bold> have not been isolated before from the title plant. The antioxidant activities and mushroom‐tyrosinase‐inhibitory activities of all compounds were determined by DPPH‐radical‐scavenging and mushroom‐tyrosinase‐inhibitory assays (<jats:italic>Table 2</jats:italic>).