Customer satisfaction is the feeling of the customer after comparing what is received with expectations. If the service provided meets customer demand, the customer will feel satisfied and tend to buy back the product and reuse the services provided.Customers who feel dissatisfied with the quality of services provided will automatically tell others and move to other business actors or companies. he research is conducted at Holyduck Medan and aims to determine and analyse the impact of Service Quality on Customer Satisfaction. Based on the experience, since Holyduck Medan is still considered as a new comer in the restaurant industry, the writer find that there is a problem in the service quality area This research the writer use quantitative method and convenience sampling where all customers of Holyduck Medan as the population and 50 respondents. This Study uses primary data sources from direct observations and questionnaires were distributes to the Holyduck customers.The simple linear regression equation: Y = 2.647 + 0.771X. The result of coefficient of determination (R2) is 0.687. It means that the 68.7% of Customer satisfaction is influenced by employee service quality and the remaining 31.3% is influenced by other variables outside this research. The result of hypothesis z-test indicate that Zcount value obtained is 5.803 that will be compared with Ztable in amount og 1.96. Zcount(5.803) is higher than the value of Ztable (1.96). Therefore, hypothesis alternative (Ha) is accepted that employee service quality has significant influence customer satisfaction at Holyduck Medan. As the recommendation company have to pay more attention on their service standard in order to improve the service quality.