Bok choy (Brassica rapa L.) is a plant with high economic value and is often consumed by people but has problems in its cultivation in the field. Land conversion results in many issues in the farming of this plant, hence plant factory and hydroponics system are a viable alternative which can affect growth and phytochemical contents which affect antioxidant activity. Hence, research is needed to discover the difference in growth, phytochemical content, and antioxidant activity. This research compared the growth of bok choy plants grown in plant factory, hydroponics in greenhouse, and soil. Extracts from the leaves of bok choy produced in each agriculture system were then analyzed using GC-MS (Gas Chromatography-Mass Spectrometry) and antioxidant activity analysis was done using DPPH (2,2-diphenyl-1-picrylhydrazyl) test. Bok choy plants grown hydroponically in a greenhouse showed the greates growth and greatest number of phytochemicals, followed by bokchoys grown in plant factory, and bokchoys grown in soil. Additionally, bokchoys grown hydroponically in a greenhouse had highest number of phytochemicals detected, however bokchoys grown in a plant factory showed the strongest antioxidant activity.