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Thirteen compounds were isolated from the <i>Canavalia lineata</i> pods and their inhibitory activities against human monoamine oxidase-A (hMAO-A) and -B (hMAO-B) were evaluated. Among them, compounds <b>8</b> (medicarpin) and <b>13</b> (homopterocarpin) showed potent inhibitory activity against hMAO-B (IC₅₀ = 0.45 and 0.72 µM, respectively) with selectivity index (SI) values of 44.2 and 2.07, respectively. Most of the compounds weakly inhibited MAO-A, except <b>9</b> (prunetin) and <b>13</b>. Compounds <b>8</b> and <b>13</b> were reversible competitive inhibitors against hMAO-B (K_i = 0.27 and 0.21 µM, respectively). Structurally, the 3-OH group at A-ring of <b>8</b> showed higher hMAO-B inhibitory activity than 3-OCH3 group at the A-ring of <b>13</b>. However, the 9-OCH3 group at B-ring of <b>13</b> showed higher hMAO-B inhibitory activity than 8,9-methylenedioxygroup at the B-ring of <b>12</b> (pterocarpin). In cytotoxicity study, <b>8</b> and <b>13</b> showed non-toxicity to the normal (MDCK) and cancer (HL-60) cells and moderate toxicity to neuroblastoma (SH-SY5Y) cell. Molecular docking simulation revealed that the binding affinities of <b>8</b> and <b>13</b> for hMAO-B (−8.7 and −7.7 kcal/mol, respectively) were higher than those for hMAO-A (−3.4 and −7.1 kcal/mol, respectively). These findings suggest that compounds <b>8</b> and <b>13</b> be considered potent reversible hMAO-B inhibitors to be used for the treatment of neurological disorders.