Background: Head nurses' Innovative work behaviors are seen as a strategic foundation since organizations must cope with increasing complexity and rapid change to have a place in ever challenging environments. In these contexts, organizations with climate conductive to innovate will be able to cope with challenges faster and get better opportunities. Aim of the study: To determine the relation between organizational climate, head nurses' innovative work behaviors and organizational innovativeness. And, to explore the role of organizational innovativeness as a mediating variable. Subjects and Methods: Research design: Descriptive correlational design. Setting: The study was executed in all inpatient medical, surgical, and intensive care units at Zagazig University Hospitals. Subject: convenient sample of head nurses who matched inclusion criteria n=288. Tools of data collection: Three tools were used for data collection as follows; Organizational Climate Questionnaire, Innovative Work Behavior Scale, and Organizational Innovativeness Questionnaire. Results: Total levels of organizational climate and head nurses' innovative work behaviors were high, while the total level of organizational innovativeness was moderate as reported by head nurses. There was positive statistically significant relation between the total level of organizational climate and the total level of head nurses' innovative work behaviors. Regarding organizational innovativeness, there were highly positive statistically significant relations with the total levels of organizational climate, and head nurses' innovative work behaviors. Conclusion: Organizational climate positively related to head-nurses' innovative work behaviors and organizational innovativeness partially mediated the relation between them. Recommendations: Maintaining hospital innovative and open to change environment to foster a positive working climate which enhances innovative work behaviors of head nurses.