The research article on “Efficiency in writing public relations materials on social media channels of ST Design Marketing Online Company”had the objectives 1.) to know the efficiency of public relations writing through social media channels of ST Design Marketing Company employees 2.) to study Guidelines for writing public relations materials through social media channels of ST Design Marketing Online Company by Quantitative survey. The researcher selected the target group to be employees of ST Design Marketing Online Company by using a questionnaire in the form of Google From, 40 people for qualitative survey (interview). The researcher has selected the target group as employees in the Creative Content department of ST Design Marketing Online, 3 people. In-depth interviews about efficiency of public relations writing and how to effectively write public relations through online media channels The results in the first objective is that effected in writing public relations materials through social media channels of ST Design Marketing Online Company found that employees in the company who are effective in writing public relations materials on social media channels. Objective 2. Guidelines for writing public relations media concerned about the content that must be short, concise, easy to understand, and knowledge of the correct terminology. It is necessary to study the rules of public relations writing on Facebook pages. To reduce the risk that the Facebook page will be closed and the most important part to make the most effective writing of public relations and to understand the identity of the customer's page. As a result, writing public relations materials can reach the target group as the customer need and knowledge gained from this research that can be utilized for work related to writing public relations materials in order to develop the ability to write public relations materials. The knowledge gained can be applied for work in the future.