The Office of the Commissioner of Baseball announced the suspension for violating the Minor League Drug Prevention and Treatment Program.
Lambo is 10th in the Southern League with a .342 batting average and fifth with a .566 slugging percentage. He has two homers, two triples, seven doubles, 13 RBIs and 16 runs scored in 19 games.
The 21-year-old California native was the Dodgers' fourth-round pick in the 2007 First-Year Player Draft. He was a 2008 Midwest League midseason and postseason All-Star and played in the Southern League All-Star Game last summer.
"The Dodgers are disappointed to learn of this news and we fully support Major League Baseball's drug policy and its penalties," the team said in a statement. "The organization does not condone the use of any substance not sanctioned by MLB's medical staff."
Lambo is the 13th player suspended this season under the Minor League Drug Prevention and Treatment program.