This report describes the evaluation of the psychometric and clinimetric properties of nine self-report measures completed by informal care partners of individuals with mild cognitive impairment or dementia in Parkinson’s disease and dementia with Lewy bodies. One hundred thirty-six care partners completed measures on relationship satisfaction, burden, stress, mood, resilience, health, quality of life, and feelings related to care provision. Psychometric properties, such as internal consistency, convergent validity, floor and ceiling effects, completion rate and data missingness, as well as clinimetric properties, such as time to administer, ease of scoring, readability and availability of the scales, were examined. Additionally, the design of the measure development studies was assessed with the 2018 COnsensus-based Standards for the selection of health Measurement Instruments (COSMIN) Risk of Bias checklist. Participants were mostly married women (>85%) with a mean age of 69.4 years. The methodological quality of the design of all measure development studies was “inadequate.” Five widely applied measures (Zarit Burden Interview, Hospital Anxiety and Depression Scale, Short Form 12 Health Survey, Relatives’ Stress Scale, and EuroQoL-5D) and two less researched instruments (Brief Resilience Scale and Relationship Satisfaction Scale) had high internal consistency and completion rates, moderate to strong convergent validity, low missingness and floor effects, and excellent clinical utility ratings. Two scales (Dyadic Relationship Scale and Family Caregiving Role) received poor psychometric ratings, and their usage among informal care partners is not recommended. In conclusion, well-validated and widely used measures received strong psychometric and clinimetric ratings. Future studies are required to determine the most reliable, valid and robust caregiver-reported measures.