The study aim was to establish the effects of organization culture and Organisation performance in management decision making a case study of Airline ‘‘A’’, with the objectives being to establish how organization culture affects employee in management decision making at Airline ‘‘A’’ and to establish how organisation performance affects employee in management decision making at Airline ‘‘A’’ This study adopted contingency theory and empowerment theory. The research design adopted was a descriptive research design that is cross sectional in nature. The study target populations were 170 staff at Airline ‘‘A’’. Questionnaires were used for data collection. The data was analysed by use of simple statistics and inferential statistics. The data was presented using tables, charts and graphs. Data was first coded and organized into concepts from which generalization was made of entire population. The conclusion drawn from the study findings were that employee involvement is been practiced in the case study organization and has a significant effect on both the employee and the organization. The study established organization culture is one of the important factors that help employee in management decision making as well as organizational performance. The study suggest the following recommendations for improvement, Airline ‘‘A’’ Management should be align organization culture and strategy. Management of Airline ‘‘A’’ should focus more on adhering to organization mission by ensuring that employees are conversant with mission and visions of the organization.