Viollet Salon, based on a Smethwick industrial estate, was handed the fine yesterday after police were called to reports of a large wedding on October 10.
When officers arrived at NSA House on Cornwall Road they found around 70 people inside despite coronavirus rules preventing groups of more than six people gathering.
An investigation was launched and the owner was served the £10,000 fine for facilitating the event.
The banqueting suite has also been banned from holding events by Sandwell Council, who said the business owner had been warned several times.
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It comes after a household in Wolverhampton this week became the first residential property in the West Midlands to be fined £10,000 after hosting a christening with dozens of guests.
Sandwell Council's interim leader, Councillor Maria Crompton, said: "Nobody wants to see Sandwell business activities shut down and obviously the council would prefer to be supporting them to operate legally - but this is particularly irresponsible given the very high infection rates in the Smethwick area.
"This action is a clear signal to all our businesses that we will not hesitate to use all powers available to enforce the rules around safety and public health and I urge them all to heed the warning."
Meanwhile a shisha lounge in the West Midlands has been shut down after it was found with 150 people inside just days after being hit with a £10,000 fine for an earlier breach.
A closure order has been issued to Kasablanca in Highgate, Birmingham, after officers forced their way in to the venue at 1am on October 24 to find more than 150 people still inside.
WATCH footage of the raid here:
Video footage shows how people poured out of the venue when police broke open the doors after being refused entry.
Earlier this month, staff had pulled down shutters at Kasablanca when officers arrived.
They found crowds gathered inside with no social distancing. The order is reviewed every week by the local authority, and the venue will have to have prove it is complying with the law before it can open again.
Chief Superintendent Andy Beard said: “It’s unacceptable that these businesses continue to flout the law, putting lives at risk and increasing the risk of infections as this deadly virus continues to spread.
“This is a difficult time for everyone, but we won’t be able to control this pandemic and return to a sense of normality if this continues to happen.
“We all need to help stop the spread of coronavirus, and no one is above the law when it comes to that.
"The vast majority are following the guidelines and we want to say thank you to those people making those personal sacrifices.
"We’re continuing to work with local authorities across the region to tackle this virus and help to protect those who live work and visit the West Midlands in the coming weeks and months."