The Total Ozone Mapping Spectrometer (TOMS) on board Nimbus 7 is used to infer the ultraviolet (UV) surface and cloud reflectance at 370 nm. Cloudless surface reflectivity was analyzed on a global basis for all surface types for several months. The UV surface reflectivity varies from 2% for some forest and grassland regions to 14% for some sandy desert areas. A notable exception is the large salt flats of Bolivia, which have a reflectivity of ~60%. Cloud reflectivity was also analyzed for clouds located at three levels in the atmosphere, as determined by the 11.5-μm channel of the Temperature Humidity-Infrared Radiometer. Average cloud reflectivity at 370 nm ranges from 52% for low clouds (tops 7 km at the equator, decreasing to >4 km at poles). ¿American Geophysical Union 1987