PDAM Tirta Moedal Semarang is a monopoly company which distributing water in Semarang Region. This company has eight departments; which are Transmission and Distribution, Research and Development, Finance, Officialdom, Secretariat, Supplies, Planning and Evaluation, Equipment and Maintenance, and Production. The employees consist of the permanent employee and outsourcing employee. PDAM applies organizational culture to increase employee’s performance but their employee can not achieve target of pervormance. The purpose of this research was to analyze the influence of Organizational Culture (X) towards the Employee’s Performance (Y) on Transmission and Distribution Division at PDAM Tirta Moedal Semarang. There are two variables used in this research, such as organization culture and employee’s performance. Sample of this research was 31 employees of transmission dan distribution divison. The methods of colecting data used interview, quesionaires, observation, and literature studies. Analizing tools used in analyzing data were, descriptive statistic, and simple linier regression. The result of the analysis showed organizational culture significantly influence positively towards employee’s performance. The employees already provided a good service , but has not reached the target. It suggested that supervisior should control employee’s work, and give motivation training order to boost their performance.