The objective of this study was to demonstrate and assess the effectiveness of hybrid aeration system and to identify how equipment improvements and operational adjustments will impact the efficiency of the aeration process. Evaluating of oxygen transfer rate and oxygenation capacity were the functions to assess such system's efficiency. Periodical runs, with enhancement of two laboratory glass basin model with (58) liter for each were conducted , one was for water and the other for wastewater where D.O analysis were taken stimulatingly at peered time intervals. Speed mixing and air discharge were the main parameters that used in detecting system efficiency. The study showed that the best result was obtained at air discharge about ( 1490 ml /min. ) and mixer (50 RPM), that alpha factor and oxygenation capacity were (1.12) and (43.2 mg O2 /L . min.), respectively. However, the study concluded that increasing mixing speed and air discharge may affect conversely on bubble size and consequently on oxygen transfer rate in aeration systems of wastewater treatment plant.