Background: The single most important test performed in blood banking services is the determination of ABO blood groups to avoid mismatching transfusion reaction and death.

Objective: The current study was undertaken to determine the pattern and distribution of the ABO and rhesus (Rh) blood groups among Hail population living in different cities of Hail.

Material & Methods: ABO and RH blood grouping test was carried out on 600 Saudi participants from different cities of Hail province namely Hail, Baqaa, Al-shanan, Al- hayat and Al-gazalh.Blood samples were collected by finger prick and tested for the blood groups by routine slide method.

Results: Group O was found the highest (51.3 %), followed by B (26.2%), A (19.2%), and AB (3.3%) while the percentage of RH Positive (95.5%) was greater than RH negative (4.5%).

Conclusion: The current study could have significant implications for the major blood banks in Hail area where certain blood groups are needed more than others in emergency conditions. In addition, the data recorded would be helpful to researchers to clarify the factors responsible for the observed distribution patterns of the studied blood group systems.