Different wild plants commonly used in folk medicine, such as different species from the genus Lathyrus, may represent new sources of biologically active compounds. Hence, a study of the composition and (bio)chemical behaviour of extracts from these plants may provide valuable information. To evaluate the phytochemical profile, and the enzyme inhibition and antioxidant activities of the aerial parts of L. pratensis and L. aureus, extracts from both plants were analyzed by high-performance liquid chromatography with electrospray ionization mass spectrometric detection (HPLC-ESI-MSn). The in vitro antioxidant activity (phosphomolybdenum, β-carotene bleaching, DPPH, ABTS, FRAP, CUPRAC and metal chelating) and enzyme inhibitory activity (acetyl cholinesterase, butyrylcholinesterase, tyrosinase, α-amylase and α-glucosidase) were also investigated for these Lathyrus species. Flavonoids and saponins were the main groups of compounds detected in the extracts from both plants. Generally, the methanol and water extracts presented remarkable antioxidant and enzyme inhibitory effects; all the observed results are critically discussed. The content of organic compounds and the antioxidant and enzyme assays suggest that these plants may be further used in phytopharmaceutical or food industry applications.