The purpose of this study was to purify the phytoconstituents and to explore the antibacterial, antifungal, phytotoxic and cytotoxic potential of dichloromethane and methanol extracts of aerial and root parts of Trigonella polycerata. The phytochemical study on methanol extract of aerial parts of the plant led to the isolation and purification of seven compounds that were identified as 3,4-dimethoxycinnamaldehyde, Trigocoumarin, 6,7,8-trimethoxycoumarin, Penduletin, 5-hydroxy-3,6,7,4´-tetramethoxyflavone, 3,5,7-trihydroxy-6,4-dimethoxyflavone and 5-hydroxy-4,7-dimethoxyflavone. These structures were elucidated by interpretation of EI-MS and NMR spectral data. The plant aerial parts methanol extract (TPAM) demonstrated higher antibacterial (78.99%), phytotoxic (85% growth regulation at 1000μg/mL) and cytotoxic activities (LD50: 45.643μg/mL). While the methanol root extract (TPRM) was highly active against bacteria's; Salmonella typhi (71.56%), Staphylococcus aureus (70.15%), Escherichia coli (69%), fungi like Candida albicans (70.21%) and moderately active against Brine shrimp larvae (LD50: 125.663μg/mL). The dichloromethane aerial (TPAD) and root (TPRD) extracts exhibited significant antibacterial (78.03% and 50.21% inhibitions respectively) and phytotoxic (55% growth regulation at 1000μg/mL) potential. Only TPAD indicated the best inhibition against fungi; Aspergillus flavus (75.31%) and moderate inhibition against Microsporum canis (42.21%). This phytochemical and biological work is the first time reported in Trigonella polycerata.