Court of Queen's Bench Justice Brian Scherman has ordered the group's president, Robert Doucette, to schedule a meeting for no later than Jan. 23.
The federal government halted funding to the group in November because of its failure to hold an assembly, as required under its funding agreement.
The judge said the group is obligated to hold two legislative assemblies and one general assembly each year, but hasn't done so since 2010.
He ruled that council members need to hold a two-day meeting to set a date for an assembly and discuss their issues democratically.
"Read your constitution and focus on the big picture," Scherman wrote in his decision on Dec. 22.
"I remind the parties that (Metis Nation-Saskatchewan) was created to be a democratically governed political action group committed to the betterment of the Metis people of Saskatchewan."
Doucette had asked the court to intervene in the group's ongoing struggles and the judge agreed.
"While the courts are reluctant to intervene in the internal affairs of voluntary organizations," Scherman said, "the matters here have a significant impact on a significant number of people."
The judge described how the group has been divided into two camps, one supporting Doucette and the other backing vice-president Gerald Morin.
Morin has said several council members are concerned about an overhaul of the group's governance structure and that Doucette is acting secretive. They want financial reporting and accountability measures, said the judge.
He said he doesn't understand what led to the "present toxic situation" with the group but the solution needs to involve democratic meetings.
"The democratic decision-making process must be respected at all levels within the Metis Nation Legislative Assembly or the present death spiral will steepen and the organization will be torn apart."
Documents obtained earlier this year by The Canadian Press revealed that the Saskatchewan group and Metis Nation British Columbia were audited in 2012 after questions arose about their management and finances.
Both organizations have said that they have since dealt with the issues raised in the audits.