Khadra Abdywahab Yusuf, 33, and Osama Abubakar Abdullah, also sold tobacco products without the statutory health warnings from Cleopatra Lounge in High Street, and failed to register their food business.
Willesden Magistrates Court heard the pair turned a blind eye to customers smoking shisha pipes inside the café despite Yusuf being convicted of doing so last year.
Environmental officers handed out fixed penalty notices to offending customers during their visit in May this year.
Yusuf and Abdullah were fined £2,000 each for allowing smoking in an enclosed area and a further £4,000 each for two offences of supplying tobacco products without the statutory health warnings.
Kudbale Ltd, the company behind the café, was fined £2,500 for each of the two offences of supplying tobacco products and £5,000 for failing to register their food business.
Cllr George Crane, lead member for environment at Brent Council said: “This is the second time within the space of a year that the owners of Cleopatra Lounge have been found breaching the law for numerous offences.
“Smoking in enclosed places damages the health of staff and non-smoking customers and supplying tobacco products without health warnings is irresponsible and illegal.”
The café, which is popular with member of the Somali community, was closed down by Brent Police in October following claims that customers were dealing drugs and embroiled in violent fights.
It is due to reopen on January 9.
Source : Kilburn Times