Nguyen Buu Loc, 38, Trinh Anh Tu, 52, Nguyen Huu Hieu, 18, and Vi Van Quyet, 44, were caught red-handed while trading in stolen dogs early on Sunday, police stated.
The four resisted arrest, wielding weapons to stave off police, who impounded several vehicles and equipment, along with the stolen dogs, which weighed over a ton.
The gang has been stealing 400-500 kg of dogs within a single night, selling them for up to VND30 million ($1,300), police said.
The investigation remains ongoing.
Vietnam consumes an estimated five million dogs a year, second only to China's 20 million. Many dogs found on restaurant menus are stolen pets sold to small, unregulated abattoirs.
Dog theft is treated as a crime only when the number of dogs stolen is valued at more than VND2 million ($86). Vietnam has no law against trading in or consuming dog meat.