He said that between 2002 and 2012, Modi had filed election affidavits while contesting Gujarat assembly elections where he had not mentioned his marital status.
"He has not informed the country about this fact. Now, while contesting from Vadorara Lok Sabha seat, he has mentioned that he is married," Sibal said.
He said the EC has assured to examine his plea.
Earlier on Friday, Congress vice-president Rahul Gandhi raked up the issue of Modi's marriage to hit out at BJP, saying while the party made claims of ensuring safety of women, it took several elections for its prime ministerial candidate to mention the name of his wife in the poll affidavit.
"Don't know how many elections he has contested till now, but he has revealed for the first time that he is married. In Delhi, he talks about honour of women but his own wife's name doesn't reach the affidavit," Rahul said.
Modi has for the first time declared himself as a married man by revealing his wife's name as Jashodaben in an affidavit filed before the Election Commission along with his nomination papers for Vadodara Lok Sabha seat.