Objective To develop the nursing competence assessment scale of caregivers of patients with middle and advanced Parkinson′s disease and test its reliability and validity, so as to provide a tool for accurately assessing the caring ability of family caregivers. Methods Based on the theoretical framework of the "caregiver skills model" developed by Farran et al., the initial scale was developed through the literature research method, the semi-structured interview method, expert consultation, preliminary experiment. Using convenience sampling method, 218 caregivers were selected and investigated, and the item analysis and reliability and validity test were conducted to form a final scale. Results The final version of the scale included 5 dimensions, namely disease cognition and coping ability, need-based nursing skill, basic nursing skill, the management of self-needs and resource utilization, with 28 items in total. The final exploratory factor analysis extracted five main factors, and the cumulative variance contribution rate of the five main factors was 68.777%. The item-level content validity index ranged from 0.857 to 1.000. The scale content validity index (S-CVI/Ave) was 0.980. The Cronbach′s alpha coefficient of the total scale was 0.943, and the split-half reliability was 0.866. Conclusion The process is scientific and reasonable. The scale has good reliability and validity and it can be used to measure the caring ability of caregivers.