Rick Hanson, who took over the top job in 2007, announced Wednesday that he'll step down as of March 13.
"I had my 40th anniversary on the job three weeks ago. In other words, two-thirds of my life has been spent in policing," Hanson told a news conference.
"This job is overwhelming. I want to sit back and evaluate what it is exactly that I want to do, where I want to go. I know if I'm ever going to do anything else, it's now."
Hanson, 60, joined the Calgary Police Service in 1975. He served with the Alberta RCMP as chief superintendent in charge of integrated and federal policing before returning to the southern Alberta city as chief.
Hanson wouldn't answer when asked whether he had any interest in politics.
"I'm not going to speak about anything that I plan to do after two weeks from Friday. I'm not going to speculate any further than that."
Hanson did say it was unlikely that he would be making a move to another police force.
Calgary Mayor Naheed Nenshi said he was saddened by Hanson's decision.
"I've often said he's the best chief in Canada and I'll say today he's the best chief anywhere."
Hanson suggested he received plenty of credit over the years for the hard work they accomplished.
"As a police chief, you're a little bit of a fraud. The fact is officers are out there every day doing amazing work, and when they do great work, it's the chief that hears about all the good things.
"I hope everyone understands the level of commitment in this police service. .. is second to none anywhere."
Alberta Justice Minister Jonathan Denis thanked Hanson for his commitment to policing.
"I appreciated the positive relationship we developed while serving our province together, and I very much enjoyed working with him over the past several years on various initiatives to make Calgary a safer place to live, work and raise a family."
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