"They're suspended from the first team for ruining the atmosphere in the club and for violating our rules ... by coming home later than allowed," CSKA coach Luboslav Penev told a news conference.
The bans, which came after their 2-0 away loss to Litex Lovech, followed media reports that several CSKA players had been spotted drinking in the early hours at nightclubs twice in the last 10 days.
"I have never stopped saying since March (when Penev took charge at CSKA) that training sessions would be hard and that's why players should take enough rest to be ready for the next day," the coach said.
Penev said that according to club rules players should be home by half-past midnight on weekdays and by 2.30 am. after a match.
"If we're to going to war, I need soldiers, I need stalwarts," he said. "We're a team who search for good results but with such unprofessional behaviour this is not going to happen."
Five Bulgaria internationals - goalkeeper Ivan Karadzhov, defenders Ivan Ivanov, Kiril Kotev and Pavel Vidanov and midfielder Yordan Todorov were among the suspended players.
"We don't need players who don't take their duties seriously," said Penev, adding that the suspended players would be fined in the coming days.
Brazilian Marquinhos, Portugal's David Silva, Todor Timonov and Svetoslav Petrov were also banned.
The suspensions came three days before CSKA travel to Swiss club Basel in the Europa League.
