BackgroundGuaranteeing nursing service safety and quality is a prioritized issue in the healthcare setting worldwide. However, there still lacks a valid scale to measure the quality and safety competencies of newly graduated nurses globally.MethodsThis scale was developed in two phases. In Phase One, a literature review and three-round e-Delphi were conducted to generate the initial item pool; while in Phase Two, five experts tested the content validity of the scale. The construct validity was evaluated using confirmatory factor analysis (CFA), and the data were collected among 1,221 newly graduated nursing students between May, 2017 and August, 2017. Finally, the internal consistency reliability and test-retest reliability were tested.ResultsThe final version’s Competency Scale of Quality and Safety (CSQS) was confirmed by the CFA involving 64 items in six dimensions, including patient-center care, safety, evidence-based practice, collaboration and teamwork, continuous quality improvement, and informatics. The results of data showed that the data supported the modified model of CSQS (Standardized Root Mean Square Residual = 0.03, p = 0.053, Adjusted Goodness of Normed Fit Index = 1.00, Root Mean Square Error of Approximation = 0.007, Fit Index = 0.95, Goodness of Fit Index = 0.97, χ2/df = 1.06), and the standardized factor loadings of items were from 0.59 to 0.74 (p < 0.05). The internal consistency reliability of the total scale was 0.98, and the test-retest reliability was 0.89.ConclusionsCSQS was a valid and reliable instrument to measure the safety and quality abilities of greenhand nurses, and could be fully utilized by nursing students, greenhand nurses, nursing educators, as well as hospital nursing managers.