Reactive oxygen species (ROS) generated during aerobic metabolism cause oxidative damage leading to several disorders, ageing or cell death. Plants synthesize an array of phytochemicals having strong antioxidative properties that can delay or prevent oxidative damage. Here, we monitored the antioxidative properties of different plant parts of two high-valued, endangered medicinal plant species: Angelica glauca Edgew. (Apiaceae) and Dioscorea deltoidea Wall. (Dioscoreaceae) from Kinnaur, Himachal Pradesh, India, using DPPH (1, 1-diphenyl-2-picrylhydrazyl) and pyrogallol autoxidation assays. The underground parts (roots/rhizomes) of both the species exhibited substantially greater antioxidative activity as compared to the other plant parts. Further, of the two tested extraction solvents, methanolic extracts exhibited higher activity as compared to the aqueous extracts across all considered plant parts in both the species implying the variability in phytochemical composition of the extracts. We compared the observations with those reported earlier and discussed the potential of A. glauca and D. deltoidea as a source of natural antioxidants.