Objective: The aim of this study was to investigate antioxidant, enzyme inhibitory and cytotoxic activities of Agropyron repens and Crataegus monogyna methanol extracts with total phenolic and flavonoid contents. Materials and Methods: Total phenolic and flavonoid contents of A. repens and C. monogyna methanol extracts were measured according to Folin Ciocalteu and aluminum nitrate methods, respectively. Antioxidant and enzyme inhibitory activities of the methanol extracts were tested spectrophotometrically. Also, cytotoxic activities of the methanol extracts against DLD-1 and CCD-18Co were investigated by using Alamar Blue assay. Results: C. monogyna methanol extract with the highest total phenolic and flavonoid contents (68.13±}0.34 μg GAEs/mg extract and 36.91±}0.17 μg QEs/mg extract, respectively) had the best antioxidant activity in β-carotene-linoleic acid (IC50: 32.72±}0.15 μg/mL), CUPRAC (A0.50: 282.69±}0.25 μg/mL), DPPH (IC50: 71.69±}0.85 μg/mL), and ABTS + (IC50: 40.43±}0.55 μg/ mL) assays. A. repens methanol extract showed the highest effect against AChE (18.73±}0.47 %), BChE (37.59±}1.07 %), urease (89.18±}0.84%), α-glucosidase (6.71±}0.23 %), whereas C. monogyna methanol extract showed the highest effect against tyrosinase (30.52±}1.00%) and α-Amylase (37.24±}0.06 %). Also, A. repens (IC500: 57.38 μg/mL) and C. monogyna (IC50: 54.04 μg/ mL) methanol extracts showed close cytotoxic activity on DLD-1. Conclusion: Antioxidant, cytotoxic, and enzyme inhibitory activities of A. repens and C. monogyna methanol extracts were investigated with total phenolic and flavonoid contents in this study. The results obtained with this study strengthen the potential of the studied plants as a new source for the discovery of antioxidant, cytotoxic, and enzyme inhibitor agents.