Diane Disney Miller (born Diane Marie Disney) is the eldest daughter of Walt Disney and his wife Lillian Disney.

Miller's husband, Ronald William Miller, was CEO of The Walt Disney Company until 1984, when Diane's cousin Roy E. Disney supported Miller's ouster in favor of Michael Eisner and Frank Wells. She and her husband have seven children.

In the early-1970s, Diane and Ron Miller purchased a vineyard in Napa Valley, California. Their intention was to upgrade the property, replant to premium varietals, install new trellising and frost protection, but not to build or run a winery. Because their vineyards produced exceptional, top-quality fruit and award-winning wines for other wineries, Diane and her husband decided to construct their own winery in 1980. Since 1981, they have operated their winery, Silverado Vineyards Winery, on a tract of their Napa property.

Diane was instrumental in pushing ahead with the Walt Disney Concert Hall in downtown Los Angeles. The project was initiated with a $50 million gift from Lillian Disney but got bogged down in wrangling over costs. Diane ensured the original design by Frank Gehry went ahead, and Walt Disney Hall finally opened in 2004.