Warren Petersen is an American politician and a Republican member of the Arizona Senate representing District 14 from January 9, 2023. He currently serves as President of the Arizona Senate. He formerly was a State Representative, also representing District 12. He was elected by his peers to serve as Majority Leader from 2018–2019.

The Arizona State Senate is part of the Arizona Legislature, the state legislature of the US state of Arizona. The Senate consists of 30 members each representing an average of 219,859 constituents. Members serve two-year terms with term limits that limit Senators to a maximum four consecutive terms before requiring a one-term respite prior to running again. Members of the Republican Party are currently the majority in the Senate. There are currently 16 women serving in the Senate after Raquel Terán was appointed, making it the first time a majority of the body was composed of female members.