In the graduate thesis the author showed the imact of conflict on interpersonal communication in business. Conflict is a sign of a high-quality conversation, true mutual understanding and reasoning, and it helps us in forming our beliefs, attitudes and evaluations. Conflicts can arise between generations, within families, due to differences in interests and ways of conducting business. Graduate thesis describes the types of conflicts and causes of conflicts. The author dealt with conflict resolution techniques that are divided into direct and indirect. Selecting a conflict resolution method leads to certain outcomes regarding conflict resolution. Those can be: loss-loss, win-loss or win-win. Communication is present since the dawn of humanity. People communicate for various reasons, either for fun, to convey their ideas or to receive certain information. Communication is a verbal or non-verbal transfer of intended messages. It involves at least two persons who affect each other to a certain extent. The author gave an overview of the communication process, how the message travels from the sender to the recipient. Organizations have two types of organizational structure. These are formal and informal. The author has presented the division of business communication that consists of internal and external communication. Internal communication means communication within the organization while external means communicating with clients or business partners. The graduate thesis describes the forms of business communication that are divided into verbal and nonverbal communication. Research on the "The impact of conflict on interpersonal communication in business" was conducted on a sample of 101 respondents. The questionnaire was sent via social network Facebook, and it was conducted in february and march 2019 year. It has 21 questions. The results of the questionnaire are shown graphically. Analysis of the results of research leads to the conclusion that people rarely encounter a business conflict and think that conflicts are badly affecting interpersonal relationships. As the most common method of conflict resolution, respondents use co-operation.