Edward R. Broida, 71, a passionate art collector and major patron of the Museum of Modern Art, has died after suffering from cancer. Broida, a Los Angeles real estate developer, began collecting art in the 1970s. In October 2005, he gave MoMA a significant gift of 174 paintings by artists including Philip Guston, Vija Celmins, and Christopher Wilmarth. The gift was reported to be worth an estimated $50 million.

According to Ann Temkin, curator in the department of painting and sculpture at MoMA, the donation had a strong effect on the museum’s holdings. “We used it to bolster strong collections, and the greatest example of that is in Philip Guston works,” she said. “We owned several great paintings, but our holdings did not approach the richness of Broida’s.”

Ms. Temkin is also the curator of “Against the Grain: Contemporary Art from the Edward R. Broida Collection,” which opens May 3 at MoMA. Of her work with Broida, Ms. Temkin said: “He was extremely generous, not only literally but in his way of looking at art and of looking at the world.”

Broida had once hoped to open a small museum of contemporary art in SoHo, but the plans fell through. His donation to MoMA, however, ensured that his collection will be seen by generations. “They’re hanging in his home, and all over the world,” said his son Eric, who described Broida as “loyal, a good father.”

Broida gave another 62 artworks to the National Gallery of Art in Washington. Other paintings he auctioned at Christie’s, including a 1954 Rothko that reportedly sold for $22.4 million.