But the Media Development Authority (MDA) said it had approved a concert this time because organisers had given assurances that they aimed to highlight the HIV/AIDS issue.
"In 2005, a similar concert featuring the pop duo was disallowed because the concert was open to general members of the public," the MDA's deputy director for arts and licensing, Amy Tsang, said in a statement Thursday.
She said concert organisers have "given the assurance to MDA that the concert is targeted at the high risk groups.
"The organiser has also assured MDA that the aim of the concert is AIDS education and HIV prevention," she said.
The duo is to perform on December 13, the Today newspaper reported.
Vivian Balakrishnan, Singapore's second minister for information, communications and the arts, has said the city-state was liberalising but retained a very strong conservative core.
As part of major revisions to the Penal Code approved by parliament last month, Singapore legalised oral and anal sex between heterosexual couples but retained a law which criminalises intercourse between gay men.