Police said they were called to the 700 block of Appleby Drive late Sunday morning for a report of suspicious activity involving a firearm.
Officers said they were told a man armed with a gun had knocked on an apartment door.
He was located in another apartment, police said.
A search turned up the sawed-off rifle, which was in the suspect’s waistband, a knife and brass knuckles, police said.
The 27-year-old Saskatoon man is facing 12 charges, including possession of a weapon dangerous to the public peace.
He was also wanted on outstanding warrants from both the Saskatoon Police Service and the RCMP, officials said.