ABSTRACT Objectives Memory concerns are common among older adults. The Multifactorial Memory Questionnaire (MMQ) is a well-validated participant-reported measure consisting of 57 items across three subscales assessing satisfaction with memory, self-perceived memory ability, and memory strategy use, respectively. Because short scales are often desired to accommodate clinical time constraints and reduce respondent burden, we created and evaluated 9-item versions of each subscale (MMQ-9). Methods In Study 1, we used an optimization strategy to identify subsets of items that maximized subscale reliability in a sample of 560 adults ages 50–90. In Study 2, we examined psychometric properties of the MMQ-9 in an independent sample of 638 adults ages 51–95. Results Internal consistency, test–retest reliability, and convergent and discriminant validity of each subscale met published criteria for good measurement properties. Confirmatory factor analysis validated the original factor structure. A hierarchical series of invariance models showed excellent fit, confirming robust measurement invariance across age, gender, and education. Conclusions The shortened MMQ-9 is a reliable, valid, and invariant measure of metamemory in middle-aged and older adults. Clinical Implications The MMQ-9 is a reasonable instrument of choice when brief yet psychometrically strong measures of participant-reported memory are required for clinical assessment of patients with memory concerns.