Former Newsnight editor Entwistle, who is currently controller of editorial standards for BBC Vision, will temporarily take on the new role from January 31.
He is among a number of internal BBC candidates vying to become the permanent successor to Bennett, who will move to a new role at BBC Worldwide on February 7.
Other names thought to be in the running include BBC North director Peter Salmon and the corporation's director of archive content Roly Keating.
External candidates could include former BBC Two controller Jane Root, head of ITV Studios Kevin Lygo and Lorraine Heggessey, who left her post as chief executive of Talkback Thames in June.
The BBC has not yet been decided whether Entwistle will continue to oversee the Knowledge division in his new capacity, or delegate the responsibilities elsewhere.