The aim of this study was determination the phytochemical composition of methanolic seeds extract of Euphorbia lathyrus. Gas chromatography-mass spectrometry (GC-MS) analysis of E. lathyrus revealed the existence of the Carbonic acid, (ethyl)(1,2,4-triazol-1-ylmethyl) diester, 1H-Pyrrole,2,5-dihydro-1- nitroso, Hexanal dimethyl acetal, Isosorbide dinitrate, DL-Arabinose, Cyclopropane,1-fluoro-1-(2- bromoethenyl)-2,2,3,3-tetramethyl, ?-D-Glucopyranoside, O-?-D-glucopyranosyl-(1.fwdarw.3)-?-d-fruc, Desulphosinigrin, D-Glucose, 6-O-?-D-galactopyranosyl, Octanoic acid, Benzofuran,2,3-dihydro, 6- Acetyl-?-d-mannose, Estragole, Ascaridole epoxide, 3-Allyl-6-methoxyphenol, 4-Amino-1,5,pentandioic acid, l-Gala-l-ido-octonic lactone, y-Sitosterol, Tetradecanoic acid, l-(+)-Ascorbic acid 2,6- dihexadecanoate, Estra -1,3,5(10)-trien-17?-ol, Propanoic acid,2-(3-acetoxy-4,4,14-trimethylandrost-8-en- 17-yl), Cis-13-Eicosenoic acid, Eicosanoic acid, 3-Pyrinecarboxylic acid, 2,7,10-tris(acetyloxy)- 1,1a,2,3,4,6,7,10, Oleic acid, eicosyl ester, Butanoic acid, 4-chloro-,1,1a,1b,4,4a,5,7a,7b,8,9-decahydro- 4a, Ethyl iso–allocholate, Ethyl iso –allocholate, Olean-12-ene-3,15,16,21,22,28-hexol, (3?,15?,16?,21?,22?)- and 2,4,6-Decatrienoic acid,1a,2,5,5a,6,9,10,10a-octahydro-5,5a-dihy. The Fourier-transform infrared spectroscopy (FTIR) analysis of E. lathyrus seeds proved the presence of alkenes, aliphatic fluoro compounds, alcohols, ethers, carboxlic acids, esters, nitro compounds, alkanes, hydrogen bonded alcohols, and phenols.