Background: Nursing teamwork effectiveness is a vital aspect of the functioning of any hospital and a basic structural component of hospitals' design. Effective nursing teamwork can be predicted as one of the effectively adopted of the health services and associated with organizational commitment. Aim of the study: Determine the relation between nursing work team effectiveness and organizational commitment among intensive care units staff nurses. Subjects and Method: Research design: A descriptive correlational research design was utilized in this study. Setting: Tanta University Main Hospital in all intensive care units. Subjects: A convenience sample including all staff nurses no (332) working in previous setting. Tools of data collection: Two tools were used. Tool I: Nursing Work Team Effectiveness Structured Questionnaire that included two parts. Part 1 concerned with socio demographic data, part2 included eight dimensions of team effectiveness. Tool II: Organizational Commitment Scale that used to assess staff nurses organizational commitment. Results: Slightly less than half 45.36% of staff nurses have moderate level of total team effectiveness. More than half 62.58% of staff nurses had moderate level of organizational commitment. There is positive significant correlation between total team effectiveness and total organizational commitment between staff nurses p < 0.001.Conclusion:Staff nurses had moderate level of work team effectiveness and also organizational commitment. Nursing teamwork effectiveness has a positive influence on organizational commitment. Recommendation: Adjust hospital policies to focus hospital systems and structures on team–based rather than hierarchical. Creating continuous assessment and evaluation of team effectiveness to determine which dimensions of team effectiveness need to be improved.