Organizational culture is a very important aspect of any organization. It consists of both observable and unobservable factors that generally shape how people work, behave, interact and perform their duties. It therefore has a major role to play in determining the productivity of any organization. This study sought to determine the influence of organizational culture on productivity with organizational justice as a mediator. The first four specific objectives sought to find the influence of power, role, person and task cultures on productivity, each separately, while the fifth objective sought to determine the mediating role of organizational justice on each of the four foregoing relationships. The study was conducted in four universities in Kenya namely Strathmore, KCA, Multimedia and Technical Universities. A total of 156 staff responded. Results showed that there was a significant positive relationship between power, culture and productivity. Additionally, organizational justice had a mediating role between power, role and task cultures and productivity but no mediating effect between power, role culture and task cultures and productivity. The research recommends that power culture should be practiced responsibly without degenerating into dictatorship, in order to give direction, respect for authority and stability. It also recommends clear policies, rules and procedures in role culture to avoid role overlaps and conflicts. It further recommends the proper recognition of talents and promotion of individual achievements in a way that promotes person culture but without excluding the star performers from the rest of the team. Lastly, it recommends that task culture that promotes team work should be encouraged, but everyone should contribute within the teams. For future studies, other productivity measures are recommended, use of triangulation to collect data and possible use of other culture models like Denison’s.