The Hudson River Museum, located in Trevor Park in Yonkers, New York, is the largest museum in Westchester County. The Yonkers Museum, founded in 1919 at City Hall, became the Hudson River Museum in 1948. While often seen as an art museum due to the extensive collection of works from the Hudson River school, the museum also features exhibits on the history, science and heritage of the region.

The museum was founded in 1919 as the Yonkers Museum and contained a number of mineral specimens housed in Yonkers City Hall and was known also as the Yonkers Museum of Science and the Arts, prior to being named the Hudson River Museum. The museum used its namesake, the Hudson River, as the core of its 75th anniversary celebration in 1994. Also central to its history is the Glenview Mansion, a house built in 1877, once the home of one John Bond Trevor, and the home of the museum for 45 years from 1929  now forms a large part of the Hudson River Museum. It contains six period rooms displaying furniture and decor from that era. In 1972 it was listed on the National Register of Historic Places.

The museum is the home of the Andrus Planetarium, the only public planetarium in Westchester County. The museum first added a planetarium in 1969 to celebrate the beginning of the Space Age and the increasing interest in space and that was just one part of the museum's expansion throughout the 1960s which included the construction of expanded and more modern facilities to house its collections. The planetarium and its laser shows are credited with driving the museum's 30% increase in attendance in the early 1990s due to the appeal of the shows to all ages.

The museum's diversity is part of what led to its citation as one of the most unusual cultural facilities by the New York State Council on the Arts in 1972. It has sought to maintain this diversity and relevance amidst changes in leadership and focus throughout its history.

The diversity is also apparent in the museum's 23-acre (9.3 ha) site, on which a 2006 expansion attempted to better join the Glenview Mansion with the modern 1969 additions.

As was the case with other museums, the late 1980s were a difficult time for the Hudson River Museum when it faced a decrease in funding, uncertainties in future funding and a high level of staff turnover, leading to some instability. The museum was forced to cut back on its operating hours, cut some plans for programming, but was still able to go ahead with the expansion of the planetarium.