The men, who are all in their 30s, were taken into custody following raids in Solna, Hägersten and central Stockholm this week. A large number of plants were found and seized by police.
It was during a separate drug investigation that police received a tip off about the cannabis-growing network.
“It’s likely we will uncover more instances and there will be more arrests,” said Stockholm police spokesperson Karin Solberg to news agency TT.
“We have probably only scraped the surface,” she added.
Because the plants have not been dried or cut, police are unable to estimate the street value of the cannabis but the find is reported to be a worth a substantial amount.
The apartments raided by police had been adapted to cater for growing the cannabis plant, with specially constructed lighting, watering and protective facilities.