The latest challenge has fuelled a scandal that has already hurt his reputation.
The dispute has handed long-serving President Robert Mugabe political ammunition as he seeks to extend his three-decade rule in an election expected within a year since Tsvangirai is his main rival.
On Thursday, Nosipho Regina Shilubane, a South African woman, lodged a legal challenge to try to block the premier's wedding, the day after the high court threw out an application by another former lover to halt the ceremony.
In papers filed at a magistrates court she said she was engaged to Tsvangirai after being introduced to him by her church pastor at a hotel in South Africa in September 2009.
Shilubane, who did not appear in court, said Tsvangirai had taken her on holiday to Singapore, the Seychelles and Botswana and that the two were "still engaged to be married".
Tsvangirai's colourful private life has come under scrutiny since the death of his wife Susan in a car crash in 2009, with local media revelling in stories of his relationships with numerous women.
The other woman keen to halt the wedding – Locardia Karimatsenga – is appealing a judge's decision to reject her challenge to Tsvangirai's marriage to fiancee Elizabeth Macheka. If the wedding were blocked it would be a major embarrassment for Tsvangirai, who had been expected to invite Mugabe, his political partner in a fractious coalition formed after a disputed 2008 election, as well as some foreign leaders to the ceremony.
While 88-year-old Mugabe has been criticised for turning what was once one of Africa's strongest economies into a basket case, Tsvangirai is now being publicly questioned over his dealings with women and money. – Reuters