The tally brings the total of those who have tested positive for the virus to 790, the Health Ministry's director general Dr Noor Hisham Abdullah said in a tweet.
He said: "80 new cases of tabligh today with total of 514 linked to the Sri Petaling gathering."
The Tabligh missionary movement held a four-day mass gathering at Masjid Jamek Sri Petaling on the outskirts of Kuala Lumpur between Feb 27 and March 1, involving some 16,000 people.
They included 1,500 foreigners, with several unknowingly bringing the virus home to Singapore, Brunei and Cambodia.
The 514 linked to the mosque cluster represents 65 per cent - or nearly two thirds - of the cumulative 790 cases in Malaysia.
On Tuesday, Malaysia announced its first two deaths from the outbreak. One of them was a 34-year-old man who attended the Sri Petaling mosque meeting, and another a 60-year-old pastor from Sarawak.
Dr Nor Hisham said on Wednesday that 15 of the cases are critically ill, and 60 of the 790 cases have recovered.