The Kreis Pernau (English: Pärnu County; Estonian: Pärnu kreis, Russian: Перновскій уѣздъ, romanized: Pernovskiy uyezd) was one of the nine subdivisions of the Governorate of Livonia of the Russian Empire.

It was situated in the northwestern part of the governorate (in present-day southwestern Estonia).

The territory of Kreis Pernau corresponds to most of the present-day Pärnu County and parts of Viljandi and Rapla counties.

[1] At the time of the Russian Empire Census of 1897, Kreis Pernau had a population of 98,123.

Of these, 94.0% spoke Estonian, 3.7% German, 1.1% Russian, 0.7% Latvian, 0.4% Yiddish and 0.1% Polish as their native language.