She will be responsible for the strategic direction of BBC2's communications and the channel's output, and reports to BBC head of publicity Vanda Rumney.
Recent publicity successes include the Louis Theroux Meets ... series.
Smith is returning to the BBC after a 14-year absence. She began her career as an office trainee in 1988 and then worked as a BBC publicity assistant in documentaries.
In 1991 she moved to Thames TV as a press officer and then to LWT to work on press for factual programmes, including Jonathan Dimbleby, Kinnock - the Inside Story, Charles at 50 and Airline.
In 1996, she was seconded to the digital broadcasting group Granada Sky Broadcasting, promoting Talk TV. She then became chief press officer for Granada South before being promoted to her present role in 2000.
Smith said: 'This is a natural step for me and one that I expect to be challenging. It's too early to speculate on my full role. But the BBC is in great shape and I am looking forward to enhancing its profile and build on its strong reputation.'
Rumney said Smith was hired not only for her programme publicity experiencing but also for her work publicising both analogue and digital TV.
Smith replaces Janet Morrow who is leaving the post at the end of the month to set up her own consultancy, Franklin Morrow Communications with consultant and former BBC publicist Jill Franklin (PRWeek, 17 May).