The committee will comprise 46 members from all political groups in the assembly. The conservative European People's Party, the biggest grouping, will supply 17 lawmakers and the Socialists 13 members.
The names of the committee's members will be announced on 19 January.
Several EU countries are conducting their own probes, as is the Council of Europe, the continent's top human rights watchdog.
Allegations that the CIA hid and interrogated Al-Qaeda suspects at Soviet-era compounds in Eastern Europe first became public in November 2005.