Water resources data for the 2004 water year for Kentucky consist of records of stage, discharge, and water-quality of streams and lakes; and water levels of wells. This report includes daily discharge records for 131 stream-stations. It also includes water-quality data for 15 stations sampled at regular intervals, continuous temperature at 7 stations, and continuous water-quality at 11 stations. Ground-water levels are published for 8 recording and 22 partial record sites. Precipitation data at a regular interval are published for two sites. Additional water data were collected at various sites not involved in the systematic data-collection program and are published as miscellaneous measurements and analyses. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Kentucky.