Microgreens, that have only become popular during the last decades, are rich in phytochemicals including phenolic compounds, which act as antioxidants. The aim of the study was to examine the effects of two different harvest times (cotyledon [embryonic leaves] and 1.5-true leaf stage) of five microgreens on the bioactive compounds in terms of phenolic content and antioxidant activity. The total phenolic content ranged from 60.9 to 2153.2 mg GAE g-1 in cotyledon leaves, whereas the value varied from 96.2 to 2113.9 mg GAE g-1 in the true leaves of microgreens. Increases in the phenolic content of the first true leaves in dill and chia were detected as 57.8% and 29.6% compared to the cotyledon leaf. Among the cotyledon microgreens, the maximum phenolic content was detected in garden cress. The antioxidant capacity of the cotyledon and true leaf stages ranged between 485.4±2.3-1985.67±24.9 µg g-1 and 508.87±5.3-2393.56±12.6 µg g-1, respectively. The maximum antioxidant capacity was detected in radish followed by garden cress. The biggest variation between the cotyledon and first true leaves in the study was observed for red beetroot. This study clearly revealed the alteration in the phenolic content and antioxidant activity of five cultivars based on growth stages of cotyledonary and true leaf in microgreen form.