* Shares fall as much as 22 percent
* Warns 2014 profit may halve on Russia rouble, exports
* Warning comes as sales in main domestic market tumble (Adds restructuring, new car launch, analyst comment)
By Samuel Shen and Kazunori Takada
SHANGHAI, Dec 17 (Reuters) - Shares of Geely Automobile Holdings Ltd suffered their steepest one-day drop in 12 years, after the Chinese automaker said 2014 profit may halve due to slumping exports and currency losses from operations in Russia - its biggest overseas market.
The profit warning comes as Geely, whose parent Zhejiang Geely Holding Group Co owns Swedish car brand Volvo, suffers sliding market share at home because of increased competition from foreign rivals such as General Motors Co and Volkswagen AG.
Geely, whose profit fell 20 percent during the first half of this year largely due to weak domestic sales, expects 2014 net profit to halve from 2.66 billion yuan ($429.79 million) in 2013, it said in a statement late on Tuesday. Earlier in the day, the rouble fell at its quickest rate since the Russian financial crisis of 1998.
"Russia is a major export market for many Chinese carmakers, accounting for a big chunk of their sales. So an abrupt slump in the rouble would have a big impact on them," said analyst Li Ming of Guoyuan Securities.
Shares of Geely fell as much as 22 percent to a two-year low of HK$2.43. The stock was trading at HK$2.54, down 17 percent in the afternoon session, heading for its biggest one-day percentage loss since 2002.
Russia is Geely's biggest overseas market, accounting for about 27 percent of exports in volume terms. Weak sales in the country contributed to a 49 percent slump in Geely's exports during the first 11 months of this year.
The Zhejiang-based carmaker said it had started to restructure its operations in Russia and increase prices there to offset the impact of a weak rouble.
Analysts said the biggest challenge for Geely as well as local rivals, such as Great Wall Motor Co Ltd, was regaining share in their home market, the world's biggest.
Geely, which sells four-fifths of output in China, saw sales volume fall 26 percent in January-November, partly attributed to brand consolidation and streamlining of its sales network over the past few years.
As part of restructuring, Geely on Monday started its move upmarket by launching its first car designed by Peter Horbury, a Britain who oversaw designs of vehicles from premium brands including Volvo, Aston Martin, Jaguar and Land Rover.
"It takes a long time to change consumers' perception of a brand, maybe five to 10 years," said Yale Zhang, managing director of consultancy Automotive Foresight.
$1 = 7.7536 Hong Kong dollars Editing by Christopher Cushing