Jet bubble column is one of the methods that can be applied to reduce levels of ammonia solutions from a fertilizer industry wastewater. This study intends to evaluate the entrainment of gas volumetric flow rate, mass transfer, and ammonia removal efficiency. Process variables studied include effluent concentration (90-300 mg/L), the liquid volumetric flow rate (10-50 L/min), and nozzle diameter (8-12.7 mm). It was found that the liquid volumetric flow rate and nozzle diameter affects the volumetric rate of gas entrainment. The volumetric flow rate of gas entrainment can result in a significant effect on ammonia removal, while the ammonia concentration and volumetric flow rate of the liquid did not produce significant effects on ammonia removal. The overall volumetric mass transfer coefficients (KLa) have been calculated from obtained model and it was determined that increasing volumetric flow rate of gas entrainment have a very significant effect on KLa.