The bioactive compounds were screened by gas chromatography-mass spectrometry (GC-MS) method. Twenty one bioactive phytochemical compounds were identified in the methanolic extract of Mentha viridis using GC-MS method. The identification of phytochemical compounds is based on the peak area, retention time, molecular weight and molecular formula. GC-MS analysis of M. viridis revealed the existence of the 3,6-Octadecadiynoic acid, methyl ester, 2,5-Dimethyl-4-hydroxy-3(2H)-furanone, 4Hpyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methyl, benzofuran, R-Limonene, 2-methoxy-4-vinylphenol, 2-hydroxy-5-methylbenaldehyde, tetra-acetyl-d-xylonic nitrile, Ficusin, Phen-1,4-diol, 2,3-dimethyl-5-trifluoromethyl, n-Hexadecanoic acid, 7-Methyl-Z-tetradecen-1-ol acetate, Ethyl 9,12,15-octadecatrienoate, Methyl 19-methyl-eicosanoate, Ethyl iso-allocholate, and Tocopherol. Five new bioactive chemical compounds 3-(N,N-Dimethyllayrylammonio), 1b,4a-eboxy-2H-cyclopenta [3,4]cyclopropal[8,9] cycloundec, 5H-Cyclopropa[3,4]benz [1,2-e]azulene-5-one, 2,2,4-Trimethyl-3-(3,8), 12,16-tetramethyl-hepta deca, and 4H-Cyclopropa[5,6]benz [1,2:7,8] azulene[5,6-b] oxiren-4-one are described and may in future be suitable sources for phytotherapy purposes. Mentha viridis contain chemical constitutions which may be useful for various herbal formulation exhibiting cardiac tonic, analgesic, antiasthamatic, anti-inflammatory and antipyretic properties.