Mr Wang, one of China's most famous dissidents, who has lived in America since 1996, will step off his flight from New York to Peking at lunchtime. Ostensibly, he will be going home to pay his respects at the graveside of his father, who died in February. But the reception he receives will determine how serious the Chinese government is about a political crackdown that is seeking to wipe out all memory of the country's democracy movement and silence remaining critics through imprisonment, exile and fear.
Dissident exiles have recently been barred from returning to their homeland, being turned back at the border in what appears to be a policy of making dissidents indefinitely exiled and stateless. In the past six months at least three exiles who have managed to slip back into the country have been arrested and jailed.
Mr Wang is returning at a time when the Chinese authorities are cracking down on democracy campaigners in advance of the 10th anniversary, in June, of the Tiananmen Square massacre.
The Qing Ming festival on 5 April is the day Chinese honour their dead loved ones and has been politically charged ever since anti-government protests erupted 23 years ago.
Fellow exiles in America said that Mr Wang had told them that he wanted to go back to "sweep his father's grave", a traditional sign of respect for the dead. But his planned return is clearly also a test for Peking's resolve.
Chinese authorities refused to let Mr Wang return when his father died, heightening fears among exiled dissidents that the government was trying to neutralise the danger they posed, without the international embarrassment of a trial and prison sentence. Mr Wang wrote one of modern China's most famous anti-government petitions, published in 1974, during the twilight years of Mao Tse-tung's rule.
He spent 14 of the next 19 years in prison for campaigning for democracy, and left China illicitly three years ago on hearing that the author of a similar petition had been jailed.
On Saturday, 50 members of a banned opposition party attempted to lay wreaths in the eastern city of Hangzhou in honour of the Tiananmen Square victims, a Hong Kong-basedhuman rights group said.
One group was turned back by police but 20 of the dissidents were allowed to hold a minute's silence at a martyrs' memorial in the city. "Remember the people who gave their lives for freedom and democracy", read the wreath they left behind.