Background: Organization trust lead to higher employees involved to their job, high-quality performance, higher job satisfaction, lower absenteeism, as well as lower labour turnover which subsequently lead to higher employees' job involvement. A high level of skill variety leads to exceeding employee job workload, thus increases employee job pressure and decrease employee job involvement. Aim: This study aims at assessing relationship between organizational trust and job involvement among staff nurses. Research design: A descriptive correlational design was used. Subjects: 110 staff nurses out of150 staff nurses included in the study. Tools: Data was collected by using two tools organizational Trust questionnaire and job Involvement scale. Results: more than three quarters (77.3%) of them had a high perception level regarding the (trust to supervisor), while (26.4%) of the studied nurses had a low level of perception regarding the (trust to organization),(68.2)high job involvement level regarding (performance compatible with self –concept), while (10.9%) of the studied nurses had low job involvement level regarding (performance as a central to self-esteem). Conclusion: there was significant statistical positive correlation between organizational trust and  job involvement. Recommendations: Hospital administrative authorities should increase staff nurses' trust in the organization through conducting frequent meeting with them, sharing them in decisions, providing incentives and treating staff nurses with respect and fairness.