Background: Objective measurement of the job performance of nursing staff using valid and reliable instruments is important in the evaluation of healthcare quality. A current, valid, and reliable instrument that specifically measures the performance of nurses is required for this purpose. Purpose: The aim of this study was to determine the validity and reliability of the Turkish version of the Job Performance Instrument. Methods: This study used a methodological design and a sample of 240 nursesworking at different units in four hospitals in Istanbul, Turkey. A descriptive data form, the Job Performance Scale, and the Employee Performance Scale were used to collect data. Data were analyzed using IBM SPSS Statistics Version 21.0 and LISREL Version 8.51. Results: On the basis of the data analysis, the instrument was revised. Some items were deleted, and subscales were combined. Conclusions/Implications for Practice: The Turkish version of the Job Performance Instrument was determined to be valid and reliable to measure the performance of nurses. The instrument is suitable for evaluating current nursing roles.