Cleistanthus collinus Roxb. commonly known as ‘Garari’ in Hindi and ‘Karra' in Chhattisgarhi, is a small deciduous tree, 2-15 m tall, which belongs to the family Phyllanthaceae. Cleistanthus collinus Roxb. is a common suicidal poison. The remarkable plant possesses diuretic capabilities along with potent antiseptic, antibacterial, and antifungal attributes; hence recent research has focused on its therapeutic potential. These seeds are rich in lipid content and have high calorific value. Proximate analysis and Ultimate analysis of full-fat seed reveal Moisture – 14.01%, Ash – 2.85%, Volatile Matter – 61.59%, Fixed carbon – 21.55%, N – 1.35%, C – 54.52%, H – 8.367%, S – 0.19%. The Cleistanthus collinus Roxb. full-fat seeds are rich in mineral and nutrient content which are a rich source of Ca and K ions. Quantitatively, the primary fatty acids detected by GC-FID were nervonic acid – 28.23%, oleic acid – 21.93%, γ -linolenic acid – 16.16%, linoleic acid – 9.74%, behenic acid – 8.96%, palmitic acid – 6.64%, lignoceric acid – 4.13%, steric acid - 2.77%. The amino acid profile by HPLC result shows essential amino acids (EAA) at 26.18%. Between EAA, leucine exhibited the most elevated amino acid score among the group, with threonine, methionine, isoleucine, valine, and lysine, subsequently following in order of decreasing scores. In the complete array of amino acid composition, it is important to take note of the non-essential amino acids (NEAA) comprising 67.35%. Alanine exhibited the highest levels, trailed by glutamate, aspartate, serine, proline, tyrosine, glycine, cystine, and arginine, in descending order of abundance.