Filmon, a well-known volunteer and a member of the Order of Canada, said she intended to use her term as the Queen's representative to promote the importance of leadership and giving back to the community.
"When I reflect on my own life, I am so grateful for the opportunities to serve the public, most often as a volunteer," she said during the ceremony inside the legislature chamber.
"And I think of the importance of taking that very first step, of taking a chance and saying yes to even the smallest of requests to get involved and lend talent and time."
Filmon is a former chair of the Cancer Care Manitoba Foundation and a former board member of the Winnipeg Airport Authority. She also founded Manitoba ALIVE — a program that teaches high school students skills needed in the volunteer sector.
Premier Greg Selinger praised Filmon's record of giving her time and energy to important causes.
"Your tireless efforts in the fields from volunteerism to public service have made this province a much better place to live."
Filmon recalled learning about the Royal Family as a young girl.
"My sister Judy and I often flipped through the pages of books on the Royal Family," she said. "As young Canadian girls, we marvelled at the two sister princesses," she added, referring to Elizabeth, who would become Queen, and Margaret.
Lieutenant-governors are picked by the prime minister from a shortlist provided by a non-partisan committee.
Filmon takes over from Philip Lee, who served for six years.
Unlike Lee, Filmon has a political background that could make proceedings in the legislature potentially awkward.
She is married to former Progressive Conservative premier Gary Filmon, whose tenure in the 1990s is regularly criticized by the NDP government. The New Democrats often blast spending cuts and other measures brought in by the Filmon government, sometimes in throne speeches that are read every year by the lieutenant-governor.
A different picture of the Filmon era is now painted on the lieutenant-governor's official website. On the page that outlines the spouse biography of the vice-regal representative, Gary Filmon is touted as having had a "steady hand on the affairs of government (which) saw the province of Manitoba achieve record levels of GDP, employment, exports and manufacturing production."
The page also says the Filmon government saw Manitoba's finances "improve from a period of chronic annual deficits" — a reference to the NDP governments of the 1970s and 1980s.
The ceremony Friday afternoon saw a less-than-full turnout among legislature members, some of whom were in their constituencies for community events. A small number of Tory members were absent, while more than half of the NDP government caucus was away.