Tsai Ing-wen of Taiwan's main opposition party will become the island's first female president after the ruling Kuomintang conceded defeat in polls today, as voters turned their backs on closer China ties.

"I'm sorry... We've lost. The KMT has suffered an election defeat. We haven't worked hard enough and we failed voters' expectations," said KMT candidate Eric Chu addressing crowds at the party's headquarters in Taipei.

The vote count is continuing but live television figures from polling stations show Tsai has secured a historic landslide victory, with around 60 per cent against 30 per cent for Chu.

Support for Tsai has surged as voters have become increasingly uneasy about a recent rapprochement with China under KMT president Ma Ying-jeou, who must step down after a maximum two terms.

As the economy stagnates, many are frustrated that trade pacts signed with the mainland have failed to benefit ordinary Taiwanese.