* President Uchida steps down
* Canon forecasts Y390 bln 2012 oper profit, below consensus
* Canon Q4 operating profit 94.6 bln yen, up 14 percent
* Full-year profit 378.1 bln yen, vs 387.5 bln yen prior yr (Recasts with Mitarai's return to president's post)
TOKYO, Jan 30 (Reuters) - Canon Inc said on Monday its president Tsuneji Uchida would step down and his role would be taken on by chairman and chief executive Fujio Mitarai after the camera and printer maker forecast much weaker-than-expected earnings growth for this year.
Like other Japanese exporters, Canon, which makes 80 percent of its revenue overseas, has been buffeted by the strong yen, a weak economic outlook and the floods in Thailand, although it has been quite aggressive in countering these challenges by cutting costs and increasing automation.
"Owing to the historically high valuation of the yen combined with the effects of the earthquake and floods, all of Canon's businesses faced extremely demanding conditions throughout the year," the company said in a statement.
Canon said Uchida would resign effective March 29, to be replaced by Mitarai, who served as president from 1995 to 2006 but has since held the post of chairman.
Canon forecast a full-year operating profit of 390 billion yen ($5.1 billion) for the current year to December 2012, below expectations of a 470 billion yen profit based on the average of 20 estimates by analysts surveyed by Thomson Reuters I/B/E/S.
The company also posted a slightly better-than-forecast 14 percent rise in fourth-quarter operating profit to 94.6 billion yen, in line with consensus expectations.
Operating profit for the full year to December was 378.1 billion yen, down from 387.5 billion yen in the previous year but beating the average of 20 analyst forecasts for a profit of 372 billion yen.
Canon, which competes with Xerox in printers and Nikon and Sony Corp in cameras, aims to sell 9.2 million interchangeable lens cameras and 22 million compact cameras in the year to December, compared with 7.2 million and 18.7 million, respectively, last year.
Its shares have fallen about 18 percent since the start of last year, slightly worse than the benchmark Nikkei average's 14 percent drop.
Xerox lowered its outlook for 2012 this month, on expectations that the debt crisis in Europe would hurt its business. ($1 = 76.67 yen) (Reporting by Isabel Reynolds; Editing by Muralikumar Anantharaman and Edwina Gibbs)