Liemeer () is a former municipality in the western Netherlands, in the province of South Holland. It was merged into the municipality of Nieuwkoop on January 1, 2007.
The municipality covered an area of 30.98 kmò of which 0.76 kmò is water. Its population was 6962 in November 2006. Liemeer consisted of the communities of Nieuwveen, Noorden, Vrouwenakker, and Zevenhoven.
The former municipality of Liemeer was established as a renaming of Nieuwveen in 1994.