In Kubschütz, in the state of Saxony, the temperature was 29.4 degrees overnight.
This broke the previous record from 2003. At that time, 27.2 degrees were measured overnight on the Weinbiet mountain in the state of Rhineland-Palatinate, German media reported.
Germany has also broken daytime heat records in recent days. In Drewitz in Saxony-Anhalt, the temperature reached 41.3 degrees on Saturday.
It is expected to be cooler at the beginning of next week.
According to the German Weather Service, heatwaves have become both hotter and longer-lasting in Germany as a result of climate change.
