Michael Graves, one of the most prominent and prolific American architects of the latter 20th century, who designed more than 350 buildings around the world but was perhaps best known for his teakettle and pepper mill, died on Thursday at his home in Princeton, N.J. He was 80.

His death was confirmed by his firm, Michael Graves & Associates, which did not specify a cause. He had been paralyzed from the waist down since 2003 as a result of a spinal cord infection.

Mr. Graves was first associated with the New York Five, a group of architects who achieved cult-like stature by helping to redefine modernism in the 1970s. He went on to design projects like the headquarters of the health care company Humana in Louisville, Ky., and the Portland Municipal Building in Oregon, which exemplified postmodernism with their reliance on color and ornament and made him a celebrity.

He used his fame as a brand, designing housewares for Target while continuing to run a busy practice even as postmodernism fell out of fashion and Mr. Graves’s reputation with it. 

Since founding his firm in Princeton in 1964, Mr. Graves designed everything from office buildings, resorts and retail stores to hospitals, monuments and university buildings. His most prominent projects also included the Ministry of Health, Welfare and Sport in The Hague and an expansion of the Whitney Museum of American Art in New York, proposed in the mid-1980s, that was never realized.

Writing about the Humana building in 1985, Paul Goldberger of The New York Times called the tower, sheathed in pink granite with a solid glass shaft up the center, “a remarkable achievement — in every way Mr. Graves’s finest building, a tower that proves his ability not only to work at large scale, but to create interior and exterior details as well wrought as those of any architect now practicing.” But Mr. Graves became a household name not for his buildings but for designing more than 2,000 everyday consumer products for companies like Target, Alessi, Steuben and Disney.

When he was awarded the American Institute of Architects’ gold medal in 2000, the institute’s Eugene C. Hopkins said Mr. Graves had “brought quality designed products within reach of everyone in the country.” (He also received the National Medal of Arts from President Bill Clinton the previous year.)

This utilitarian direction arguably lost Mr. Graves some ground in his profession. “He chose to go populist and commercial,” the architect Peter Eisenman, a good friend of Mr. Graves, said in a telephone interview. “I think you pay a price for those kinds of things.”

Mr. Graves persevered nonetheless, with unabashed pride. Asked by The Times in 2011 whether he worried about injuring his reputation, he said: “Just the opposite. It was my hope to do that.”

“We have behind us all this mass production, so why not take advantage and bring the price down for everybody?” he added. “I figured, if it’s going to get designed, let’s do it well. So that’s what we did, and I’m happy about it 

Mr. Graves’s firm is celebrating its 50th anniversary with an exhibition at the Grounds for Sculpture in Hamilton, N.J., which is on view until April 5.

“For those of us who had the opportunity to work closely with Michael, we knew him as an extraordinary designer, teacher, mentor and friend,” his firm said in a statement. “For the countless students that he taught for more than 40 years, Michael was an inspiring professor who encouraged everyone to find their unique design voice.”

Mr. Graves recently helped establish the Michael Graves School of Architecture at Kean University in New Jersey.

Born in Indianapolis on July 9, 1934, Mr. Graves studied architecture at the University of Cincinnati and Harvard University. In 1962, he began a 40-year teaching career at Princeton. As one of the New York Five, he was linked with Mr. Eisenman, Richard Meier, Charles Gwathmey and John Hejduk. They were also known as the Whites, because of their proclivity for white buildings inspired by the purist forms of Le Corbusier. 

Mr. Graves became among the most celebrated of the postmodernists in the 1980s. “He was on top of the heap,” Mr. Eisenman said. The Portland building, with its hammered-copper Portlandia statues, its rich colors and its classical references, was a standout among corporate buildings. Seen by many as a rejection of — or a welcome departure from — the glass-and-steel Modernist orthodoxy, the Portland building became the centerpiece of the so-called postmodern movement.

But by 1985 the backlash against postmodernism had begun, and the rejection of Mr. Graves’s plan for expanding the Whitney Museum of Art’s famed Breuer building was a setback. “No Mo Po Mo!” became the rallying cry of foes of postmodernism. His design would have radically altered the facade of the building, prompting objections from community groups and the city’s Landmarks Preservation Commission.

“Losing the Whitney — and that fight he had with the neighborhood — took a lot out of him,” Mr. Eisenman said. “He really wanted to build that building.”

Among Mr. Graves’s later projects was the design of scaffolding used for the restoration of the Washington Monument in 2000.

After he began using a wheelchair, Mr. Graves became internationally recognized as an advocate of health care design. In a 2011 interview, he explained why he tended to use color in designing hospital rooms.

“It’s not there to get you well,” he said, “but make you smile and make you think life is not as bad as that operation you had.”

Mr. Eisenman said he and Mr. Meier had both seen Mr. Graves recently, at a luncheon at the American Academy of Arts, and noted that the declining numbers of the New York Five (Mr. Hejduk died in 2000, Mr. Gwathmey in 2009) had made him think about his own mortality.

“We had a lot of good times,” Mr. Eisenman said. “As I said to Richard Meier, ‘And then there were two.’ ”

Mr. Graves had been a member of SAH since 1979.