The 6-foot-7, 235-pound Canadian native averaged 12.5 points and 5.6 rebounds per game this past season for the Redbirds.
"I chose Oregon because I felt they were the best option for what I was looking for," McIntosh told ESPN. "They play a free-flowing offense where versatility is showcased. Also, their track record speaks for itself in their success the last few years."
The Ducks went to the Final Four last season, but coach Dana Altman lost the majority of his core players to the NBA draft. Dillon Brooks, Tyler Dorsey and Jordan Bell all left early, while Chris Boucher graduated.
McIntosh, who earned second-team All-Missouri Valley Conference honors last season and also considered Oklahoma, will be able to play immediately.