The March for Science Portland (also known as March for Science PDX and Portland March for Science) was a protest held in Portland, Oregon, on April 22, 2017 (Earth Day). It was part of the global March for Science, a series of rallies in Washington, D.C., and more than 600 cities worldwide. Organized by Portland Science Advocates, the march supported science and protested President Donald Trump's proposed cuts to funding for the Environmental Protection Agency and the National Institutes of Health. Funding for the event, which cost approximately $30,000, was crowdsourced. Amid rainy weather, thousands attended, gathering at Tom McCall Waterfront Park before marching 44 blocks through downtown Portland. Speakers included Earl Blumenauer, Suzanne Bonamici, and Elizabeth Steiner Hayward. Supporting organizations included the Audubon Society of Portland, the Oregon Environmental Council, Oregon Health & Science University, and the Xerces Society. Reporters noted organizers' efforts to create a political yet nonpartisan atmosphere, though participants publicly criticized Trump. The event featured activities for children and was described as family-friendly. The group included people from diverse disciplines, such as Jackie Wirz, an assistant dean at Oregon Health & Science University, and a store clerk with a passion for science and writing. The event's steering committee was co-chaired by Curt Waltman and Wirz; Rich Hatfield served as communications committee co-chair, and Sumi Malik, a transportation planner for CH2M Hill, served as community outreach co-chair. Alex Conley was also an organizer. The organizers met through the event's Facebook page, launched in February 2017, and sought advice from the organizers of the Women's March on Portland, held in January 2017. They aimed to support science and protest President Donald Trump's proposed cuts to funding for the Environmental Protection Agency and the National Institutes of Health, as well as his threat to withdraw from the Paris Agreement and reduce funding for scientific research and K–12 science programs, among other policies. Prior to the march, Waltman and Wirz wrote a guest column in The Oregonian praising Oregon's achievements in science and encouraging people to "stand up for science." They wrote, "We stand in support of scientific inquiry, researchers, availability of data and evidence-based policy," and invited people who "love" science to participate. Preparation and planning: funding for the event, which cost approximately $30,000, was crowdsourced. Obtaining a permit to host the event at the park cost $3,000. Monetary donations were accepted, and merchandise sales also funded the demonstration. Funds were transferred through the Xerces Society. Portland Science Advocates was established as a nonprofit organization for members to continue the demonstration's mission after the march. Prior to the march, organizers surveyed Tom McCall Waterfront Park and posted flyers about the event in the surrounding area. They emphasized that all people were invited to participate, not just scientists, and anticipated participation by approximately 10,000 demonstrators. Nearly 7,000 had committed to attending the event on its Facebook page. Organizers planned to use drones to help estimate the crowd size. More than a thousand people had gathered by 10:00 a.m. at Tom McCall Waterfront Park, near the Morrison Bridge. Six business leaders, innovators, politicians, and scientists spoke at the event. Politicians included U.S. Representatives Earl Blumenauer and Suzanne Bonamici, and Elizabeth Steiner Hayward, a Democratic member of the Oregon State Senate for the 17th District. Blumenauer referred to the Trump administration in his speech, saying, "We have failed in the political process because they've made science partisan." "They've undermined the credibility and confidence that people have, for example in science and in dealing with climate," he said. He also spoke about the importance of evidence-based decision-making. In her speech, Bonamici said science should not be a partisan issue, and told the crowd: "We are going to go back to Washington, D.C., with all of you in our minds — this beautiful sea of science supporters — and fight for research, fight for clean air, fight for clean water, and fight for our planet. Stay engaged; this is just the beginning." The other speakers included Xerces Society senior conservation biologist Rich Hatfield, Intel educator and innovation manager Shashi Jain, and Gabe Sheoships, a citizen of the Cayuse and Walla Walla tribes of the Confederated Tribes of the Umatilla Indian Reservation, who serves as education director for Friends of Tryon Creek and is an adjunct faculty member at Portland State University. At about 11:00 a.m., protesters began marching south along Naito Parkway. They navigated a 44-block portion of downtown before returning to the park around noon for a "Science Expo" and "Kid Zone," as well as live music. The route was identical to the one used during the Women's March on Portland; participants followed Naito to Jefferson Street, to Fourth Avenue, to Pine Street, then revisited Tom McCall Waterfront Park. Family-friendly educational booths and vendors were stationed near the park's Battleship Oregon Memorial. The demonstration ended at about 4:00 p.m. Amid rainy weather, thousands of people attended; some estimates far exceeded the anticipated 10,000 participants. Many protesters wore science-themed costumes, such as bio suits, space suits, and white lab coats. The city experienced increased traffic because of street and bridge closures for the march and other events.

The march was endorsed by the Audubon Society of Portland, Oregon Health & Science University, and the Xerces Society, and was promoted by the Democratic Party of Washington County, the Oregon Environmental Council, Portland State University's biology department, and Rose City Astronomers. The Center for Biological Diversity issued a press release confirming some of its scientists planned to march in Portland and other cities across the United States. The educational nonprofit Science Project had a booth at the park. The American Chemical Society, which publishes Chemical & Engineering News, supported the parent March for Science demonstration as long as organizers remained nonpartisan; the magazine's former editor-in-chief, Rudy Baum, covered the Portland march. Portland's Badass Women's Protest Choir, formed after the 2016 presidential election, also planned to attend.