Hypoxia, conditions of reduced oxygen, occur in a wide variety of biological contexts, including solid tumours and bacterial biofilms, which are relevant to human health. Consequently, the development of chemical tools to study hypoxia is vital. Here we report a hypoxia-activated small molecule-mediated gene expression system using a bioreductive prodrug of the inducer isopropyl 1-thio-β-D-galactopyranoside (IPTG). As a proof-of-concept we have placed the production of a green fluorescent protein under the control of hypoxia. Our system has the potential to be extended to regulate the production any given protein of choice.