The　processes　of　ferroptosis　and　drug-induced　liver　injury　(DILI)　correlate　closely　to　oxidative　stress　in　mitochondria　which　will　affect　intracellular　microenvironmental　parameters　such　as　lysosomal　viscosity.　Therefore,　it　is　of　great　significance　to　dynamically　monitor　ONOO-　in　mitochondria　and　viscosity　in　lysosomes　for　understanding　redox　signal　transduction　but　remains　challenging.　Here　we　report　a　near-infrared　fluorescent　probe,　HCy-OH-mito,　which　has　the　dual-organelle　targeting　ability　for　the　detection　of　ONOO-　in　mitochondria　and　viscosity　in　lysosomes　via　a　＂three-key-and-lock＂　strategy.　HCy-OH-mito　has　been　successfully　applied　to　independently　and　simultaneously　label　mitochondria　and　lysosomes　in　live　cells,　and　monitor　the　fluctuations　of　ONOO-　in　mitochondria　and　viscosity　in　lysosomes　during　ferroptosis　and　APAP-induced　liver　injury　and　in　live　zebrafish.