Maldonado represents state Senate District 15, which includes the counties of Santa Cruz, Monterey and San Luis Obispo, as well as southeastern Santa Clara County and northern Santa Barbara County.
"Senator Maldonado has proven he has the strength and courage it takes to reach across the partisan divide and put the interests of Californians first, and he is absolutely the most qualified person to take on the role of lieutenant governor," Schwarzenegger said in a statement issued this evening.
Maldonado will have to be confirmed by the Legislature before he assumes the post, in which he would earn $159,134 annually.
The 42-year-old Republican senator attended California Polytechnic State University, San Luis Obispo and was mayor of Santa Maria from 1996 to 1998. He served in the state Assembly from 1998 to 2004, when he became a senator.
In a statement released by the governor's office, Maldonado said, "Like the governor, I learned the values of hard work, dedication and personal responsibility at a young age and place a high priority on reforming California's broken government so that it is more responsive to and reflective of California's diverse population."
The lieutenant governor serves as acting governor when the governor is out of the state and as president of the state Senate.
Additionally, the lieutenant governor sits on the University of California Board of Regents, the California State University board of trustees, and the California State Lands Commission.
Schwarzenegger will hold a news conference in Los Angeles on Tuesday morning with Maldonado to formally announce the appointment.