That number breaks last Saturday's record of 14,714 cases, which was higher than usual because RKI updated their data to include cases from several days before. Germany's total coronavirus case count now stands at 449,275.
The death toll rose by 85 to 10,098, the RKI data showed.
The German Interdisciplinary Association for Intensive Care and Emergency Medicine said the number of patients in intensive care rose exponentially, to five times higher than a week ago at 1,470.
Chancellor Angela Merkel is set to discuss further measures to contain the spread of coronavirus in the country on Wednesday afternoon in a meeting with the leaders of Germany's 16 states.