Streamflow data from 35 stations in and near Alaska were analyzed for changes between the cool phase (1947–1976) and the warm phase (1977–2006) of the Pacific Decadal Oscillation. Winter, spring, and summer flow changes and maximum annual flow changes were different for glaciated basins (more than 10% glacier‐covered area) than for nonglaciated basins, showing the influence of glaciers on historical streamflow changes. Mean February flows, for example, increased for the median of available stations by 45% for glaciated basins and by 17% for nonglaciated ones.