"The purpose of this study was to investigate the effect of social support from co-workers on job performance among Jordanian hospital nurses. A correlational descriptive survey was used to investigate this relationship among a convenience sample of 365 Jordanian hospital nurses. Data were collected using a structured questionnaire, which included the Schwirian Six Dimension Scale of Nursing Performance, the McCain and Marklin Social Integration Scale, and the demographic form. Perceived social support from co-workers enhanced the level of reported job performance (r = 0.40; p < 0.001). The analysis also showed that demographic variables and co-workers support explained 20% of the variation in job performance. Results indicated the positive effect of co-workers support on job performance."