Background: Integrated marketing communication (IMC) became increasingly popular since 2005, the IMC is built of four parts. The first part is a concept and it also is the process. The second part explains that IMC needs special skill and knowledges. The third part described the IMC have three pillars which focus on audience, channel and the result. The last part refers to that IMC attempts to the increase of company communication. The concept of IMC can be called “Speak with One Voice”. The meaning of IMC includes advertising, promotion, public relations, direct marketing. CI, packaging, news media and all other communication activities within the scope of marketing activities, but also enables companies to communicate unified communicate information to consumers.Purpose: The researchers of this thesis aim to explore the barriers when organizations implement integrated marketing communication.Methodology: In this paper, authors used qualitative research under deductive approach. The primary data was gathered with six participants from different advertisement agencies. All the interviews were conducted with semi-structured interview.Conclusion: Through the preview semi-structured interviews, there are two barriers has been agreed with all of these 6 participants who are from different advertising agencies. Authors defined these two barriers as the main barriers to implement integrated marketing communication by organizations: the management knowledge and Lack of horizontal communication. Authors also have some important finding about new barriers of implementation to integrated marketing communication. Three of our participants from different adverting agency with a lot of experience on IMC mentioned that the employees' trust in leadership of managers is also one of the main barriers. Authors believe this might be another main barrier for organization on implementation of IMC and should attract enough attention by marketers.Key words: Intergrated marketing communication, barriers, management knowledge and Lack of horizontal communication