Background: Age-based cognitive deficits are exacerbated by stereotype threat effects (i.e., the threat of being judged as cognitively incapable due to aging). We tested whether age-based stereotype threat effects can occur via impair- ing older adults’ ability to select the best strategy and/or to execute strategies efficiently. Methods: Older adults (age range: 64.3–89.5 years) were randomly assigned to a stereotype threat or control condition before taking an episodic memory task. They encoded pairs of concrete words and of abstract words, with either a repetition or an imagery strategy, and then took a cued-recall task. Whereas participants in experiment 1 could choose between these two strategies, those of experiment 2 were forced to use either the repetition or the imagery strategy. Results: Our findings showed that age-based stereotype threat disrupts both the selection and execution of the most efficient, but also most resource-demanding, imagery strategy, and that these stereotype threat effects were stronger on concrete words. Conclusion: Our findings have important implications to further understand age-based (and other) stereotype threat effects, and how noncognitive factors modulate age-related changes in human cognition.