A Slippery Surface Warning Apparatus includes a Ultra-Violet Emitting Device, a Sign with Indicia, a Mounting Assembly, a Light-refracting liquid or powder to be added to a cleaning solution or other fluid, and a Light Housing. This Slippery Surface Warning Apparatus is used for the purpose of alerting people in the vicinity of a potential safety hazard whereby light emitted from the Ultra-Violet Emitting Device is directed to the slippery surface imbued with UV-Reflected cleaning solution for the purpose of showing persons where a slippery surface or hazardous condition is.