In 2006, she joined the cast of NBC's Law & Order during the premiere of the 17th season, portraying Assistant District AttorneyConnie Rubirosa. Her performance as ADA Rubirosa has been widely praised by critics. In 2007, she earned a nomination for "Best Supporting Actress-Television" by the Imagen Foundation Awards. Following in 2008, she was nominated for an ALMA Award as "Outstanding Supporting Actress in a Drama Television Series". Later that year, she garnered an "Impact Award" for "Outstanding Performance in a Dramatic Television Series" by the National Hispanic Media Coalition. De la Garza played Rubirosa for the final four seasons of Law & Order, becoming one of the longest-serving actors in the junior ADA role.
In February 2012, she was cast as a lead in the NBC medical drama pilot Do No Harm. She played Dr. Lena Solis, a neurosurgeon.
In June 2012, De La Garza was added to the cast of You Are Here, the feature film debut of Mad Men creator Matthew Weiner.
On October 28, 2013, it was reported that Alana de la Garza will be guest starring in an episode of Law & Order: Special Victims Unit as Connie Rubirosa. Rubirosa, who had previously been a Manhattan ADA, is now a Federal Prosecutor, heading up a joint task force on underage sex trafficking. It originally aired on January 22, 2014.
She married her longtime boyfriend, Michael Roberts, a writer, on May 31, 2008, in Orlando, Orange County, Florida. On September 28, 2010, de la Garza gave birth to her son, Kieran Thomas Roberts, two weeks early. On February 9, 2013, de la Garza announced that she was pregnant with a girl. She gave birth to her second child, Liv Elena, on July 7, 2013.
Charmed (1 episode, "Desperate Housewitches", 2005) as Sylvia
The Book of Daniel (3 episodes, "Acceptance", "Forgiveness" and "Temptation", 2006) as Jessie Gilmore
CSI: Miami (12 episodes, 2005–2011) as Marisol Delko Caine (also archive footage on "Rio" (2006) (uncredited), on "Out of Time" (2009), on "Manhunt" (2010), on "Happy Birthday" (2010), on "Last Stand" (2011) (uncredited), on "Killer Regrets" (2011))