When Tsai Ing-wen takes office as Taiwan's president Friday she steps onto a tightrope between voter dreams of national pride and a Beijing that wants the island on a short leash.

Tsai's election victory reflected public desire for a president who would put self-ruling Taiwan first, not "sell out" to China, which still sees the island as part of its territory.

Her political message revolves around the importance of Taiwanese identity, and has resonated with voters fed up with living in Beijing's shadow.

An eight-year rapprochement with China under outgoing president Ma Ying-jeou of the Beijing-friendly Kuomintang brought trade deals but little cheer for ordinary Taiwanese, stretched by low salaries and high living costs.

There was also growing concern that economic ties were a back-door route to the erosion of Taiwan's sovereignty.

"Tsai should take a tougher stance on China," East Lin, a 32-year-old restaurant manager from Taipei, told AFP.

"The worst thing China could do is to start a war, but that seems very unlikely. I believe Tsai can uphold Taiwan's sovereignty without causing things to worsen irreversibly."

Tsai has pledged to diversify economic partnerships and seek a higher profile for Taiwan internationally, where it is sidelined from major organisations due to Chinese objections, a sore point for many Taiwanese.

"I hope Tsai can secure more support in the international community to help Taiwan fend off China's interference," said 20-year-old college student Ken Lai.

"She should also reduce the economic reliance on China to rid Taiwan of its control so Taiwanese people can decide our future."

But Tsai will have to counterbalance the defensive role her supporters want her to play with keeping Beijing at bay.

The thaw under Ma was enabled by his acceptance that Taiwan was part of "one China", with different interpretations on each side.

Tsai, whose Democratic Progressive Party is traditionally pro-independence, has never accepted that notion, although she has pledged to maintain the "status quo" with Beijing.

- Isolation fears -

China has already been making life difficult for Taiwan since Tsai was elected in January.

Taiwanese fraud suspects have been deported from Malaysia and Kenya to the mainland in a move that infuriated Taipei, which argued they should be tried on home turf.

Tourist numbers from China have also dropped with speculation Beijing is actively turning off the taps.

China's Taiwan Affairs Office (TAO) recently said responsibility for any cross-strait crisis "must be shouldered by those who change the status quo", a thinly veiled threat to Tsai not to rock the boat.

Beijing has also warned against any attempt to formally declare independence.

Although Taiwan has developed into a fully fledged democracy since splitting with the mainland in 1949 after a civil war, it has never officially declared a breakaway.

Observers agree China relations will cool further once Tsai takes power, but Beijing is unlikely to unleash dramatic measures that would force Tsai to lean closer to Washington -- Taiwan's greatest ally and leading arms supplier.

"Tsai's priority is not to provoke China, to give it any excuse to attack, while reducing Taiwan's economic dependence on the mainland," said Fan Shih-ping, of National Taiwan Normal University.

Her vision for kickstarting the island's ailing fortunes includes developing it as a research and development hub for industries including defence and green energy, and building economic partnerships with Southeast Asia and India.

However, there are concerns frosty relations with China will be economically damaging.

"I hope Tsai can focus her energy on boosting the economy. Taiwan needs stable ties with China as it's our main trade partner and the world's biggest market," said Angelia Chen, a 44-year-old businesswoman.

Despite Tsai's reassurances, some still fear she will take things too far.

"Taiwan is weak in the international community and if she pushes for independence, Taiwan will be further marginalised" as Beijing would rally its allies against the island, said college student Kuo You-hsuan, 19.

"I hope she will maintain the status quo and peace with China."