All those charged are under 16 – with the majority aged 13 and 14. Police say daytime gang crime has been a "persistent" problem in Ruchill Park since May.
Territorialism between youths from the area and nearby Possilpark has been blamed.
Residents have found weapons stashed close to the park including knives, batons and sticks. The teenagers, all under 16, have been charged with a range of offences including possession of offensive weapons, breach of the peace and culpable and reckless conduct.
The 12 are due to appear at Glasgow Sheriff Court on August 17.
It is understood rival gangs arrange fights using Blackberry messenger. Areas around Bisland Drive and Panmure Street have been identified as trouble spots. Officers using CCTV cameras have been monitoring activity in the park for the past two months with increased patrols, including mounted police.
Police have been working in partnership with Maryhill Housing Association and North Glasgow Housing Association to target the violence.
Chief Inspector Ann Hughes of Maryhill Police said: "This is about keeping a community safe and sending a message out that this behaviour will not be tolerated.
"I am a mum myself, and I would appeal to parents. It is about knowing where your child is and encouraging them to take part in worthwhile activities."
The police tactics reflect a new strategy by the Gangs Task Force, which began in 2008. The squad now arrests suspects early in the morning. Before this, officers charged youngsters in front of their parents, but this was seen as a soft touch approach.
North Glasgow Communities provides a range of activities for young people in the area including those who have been involved in crime. Jill Mackay, project manager, said: "It's a complicated problem and it's not just Ruchill.
"There aren't enough jobs and opportunities. The situation is getting worse. Young people have that sense of not being supported.
"There needs to be a major rethink about the opportunities available to young people, not just short-term training."
Police say daytime gang crime has been a "persistent" problem in Ruchill Park