Witness testimony has twice been delayed in the long-awaited trial due to problems with disclosure of evidence.
The U.N. court announced Friday that the trial will run from July 9 to 20, then pause for three weeks during the tribunal's summer recess.
Mladic faces 11 charges, including two of genocide, for allegedly masterminding atrocities by Serb forces throughout the 1992-95 Bosnian war. He denies wrongdoing.
If convicted, he faces a maximum sentence of life imprisonment.
Mladic was arrested last year in Serbia after 15 years as one of the world's most-wanted fugitives.