Winslet, 37, said 'I do' in a hush-hush ceremony about which even the parents of the bride and groom were not informed, reports thesun.co.uk.
Winslet's spokeswoman has confirmed that the Oscar-winning actress is married to Rocknroll.
They had invited only a few friends and the actress's children from two previous marriages with director Jim Threapleton and Sam Mendes.
When Winslet's father Roger was asked about this, he replied: "What are you going on about?"
Rocknroll's father Robert said: "It's not something I know of - but nothing would surprise me with those two."
"It was a really romantic, private ceremony," a source said.