Iris kashmiriana belongs to the family Iridaceae and is an important endemic medicinal plant of Kashmir. The current study was designed to determine the phytoconstituents, antioxidant, and cytotoxic potential of ethyl acetate (IRK-ETH) and methanol (IRK-MTH) extracts of Iris kashmiriana flowers. IRK-MTH extract demonstrated maximum radical scavenging activity in DPPH, ABTS, and Superoxide anion radical antioxidant assays with IC50 values of 73.15 μg/ml, 79.05 μg/ml, and 86.52 μg/ml respectively. IRK-ETH and IRK-MTH extracts possessed phenolic (70.9 and 208.5 mgGAE/gdw) and flavonoid (487.7 and 40.55 mgRE/gdw) contents respectively. In MTT assay IRK-ETH demonstrated the highest cytotoxicity towards the MCF-7 cell line with a GI50 value of 49.13 μg/ml. Phase contrast and fluorescence microscopic studies in MCF-7 cells revealed that IRK-ETH extract caused condensation of chromatin, rounding of cells, and nuclear condensation in cells which shows the apoptotic potential of the extract. GCMS analysis for phytochemical characterization revealed the presence of 9 compounds in both extracts which have been reported to possess antibacterial, cytotoxic, and anti-oxidant activities. HPLC analysis confirmed the presence of different polyphenols in both extracts with IRK-MTH extract having maximum polyphenols like epicatechin, rutin, quercetin, vanillic acid, sinapic acid, caffeic acid, chlorogenic acid and ellagic acid. These findings suggest that the flowers of Iris kashmiriana possess very good antioxidant and cytotoxic potential owing to its rich phytoconstituents.