| Alexandrine of Prussia | |
| Succession: | Grand Duchess consort of Mecklenburg-Schwerin |
| Reign: | 1 February 1837 – 7 March 1842 |
| Birth Date: | 23 February 1803 |
| Birth Place: | Berlin, Prussia |
| Death Place: | Schwerin, Mecklenburg-Schwerin |
| Consort: | yes |
| Spouse: | Paul Frederick, Grand Duke of Mecklenburg-Schwerin |
| Issue: | Frederick Francis II, Grand Duke of Mecklenburg-Schwerin Louise, Hereditary Princess of Windisch-Graetz Duke William |
| Full Name: | Friederike Wilhelmine Alexandrine Marie Helene |
| House: | Hohenzollern |
| Father: | Frederick William III of Prussia |
| Mother: | Louise of Mecklenburg-Strelitz |
Alexandrine of Prussia (Friederike Wilhelmine Alexandrine Marie Helene; 23 February 1803 - 21 April 1892) was Grand Duchess of Mecklenburg-Schwerin by marriage to Grand Duke Paul Frederick. She was the daughter of Frederick William III of Prussia and Louise of Mecklenburg-Strelitz.
Born on 23 February 1803 in Prussia, Alexandrine was the seventh child and fourth daughter of King Frederick William III of Prussia and Duchess Louise of Mecklenburg-Strelitz.
On 25 May 1822, after rejecting a marriage proposal from the future King of Sweden, she married Paul Frederick of Mecklenburg-Schwerin. In 1837, Paul Frederick succeeded his grandfather as Grand Duke of Mecklenburg-Schwerin, making Alexandrine the Grand Duchess of Mecklenburg-Schwerin.
The marriage was generally considered unhappy;< Paul Frederick was a military man who had little time for or interest in his wife and family. Alexandrine, by contrast, was a devoted mother who tenderly raised her children and actively cultivated their cultural pursuits. Alexandrine herself was very cultured but was also described as a stereotypically-remote German princess. She was not considered an intellectual but attended scholarly lectures and read many books.
On 21 April 1892 in Schwerin, Alexandrine died at the age of 89. She was buried at the Schwerin Cathedral.
At the time of her death, she was the last surviving grandchild of King Frederick William II of Prussia. She outlived all three of her children and would die in the reign of her grandson, Grand Duke Frederick Francis III.