Hanjeli, a functional food plant still rarely known to the general public, with the Latin name Coix lacryma-jobi L with the variant ma-yuen. Hanjeli has fruit seeds that can be used as a nutritious food source and have biological activity. This study aimed to record the nutritional content of hanjeli seeds and evaluate the antioxidant activity and alphaglucosidase inhibitor activity as antidiabetic. Hanjeli seeds were evaluated for their nutritional profile by analyzing the proximate, mineral, phytoconstituent, and total phenolic and flavonoid contents of hanjeli seed extract. The extract was tested for antioxidant activity with DPPH radical reduction, ABTS and iron reduction (FRAP) parameters, and antidiabetic evaluation with alpha-glucosidase inhibition parameters. The results of the nutritional content analysis show that the macronutrients and micronutrients (minerals Na, K, Ca, Mg, and Fe) were by Indonesia Standard National. Hanjeli seed extract contains phytoconstituents in phenolics, flavonoids, saponins, alkaloids, and terpenoids. Total phenolic and flavonoid levels were 98.17±0.053 mg EGA/g extract and 15.36±0,068 mg EQ/g extract, respectively. Hanjeli seed extract has antioxidant potential in reducing DPPH and ABTS radicals with an IC50 of 662.69±2.77 and 164.053±0.156 µg/ mL, respectively, and an iron-reducing power (FRAP assay) of 70.21±0.93 µM/g extract. Hanjeli seed extract showed strong potential in inhibiting alpha-glucosidase with an IC50 value of 84.47 µg/mL. The nutritional content and biological activity of hanjeli seeds showed promising potential to be developed as functional food products for the public. © 2025 The Authors. Published by Rynnye Lyan Resources.