The objectives of this research were to study 1) the internal communication model 2) The use of social media by personnel 3) Work efficiency within the organization. The sample group was the Office of the President. Bunditpatanasilp Institute, 128 people. The research tools were questionnaires, data analysis using statistical software package. Statistics for data analysis were percentage, mean and standard deviation.

           The research findings were as follows: 1) the internal communication style: Top-down communication style It is used to a large extent It is a communication from the supervisor to the operator. To notify important information or policies in the operation within the organization to the personnel. Bottom-up communication style It is used to a large extent It is a communication from operators to supervisors. Able to check the work as a result of the work that has already been assigned. Horizontal communication format It was used at high levels is that personnel in the organization Have a conversation and communicate to coordinate. request information or receive information from the organization can exchange attitude information and jointly solve problems in operation and cross communication style It was used at high levels. is a shortening of time and steps to work Because some jobs are unable to wait for line communication. 2) The use of social media by personnel Personnel can find information and contact work more conveniently through social media such as Line, Facebook, E-mail, etc. Social media can be used to help connect with the work team quickly. Encourage others in your team to use social media to communicate more. Because there is no cost and convenience. Reply to questions or send assignments to colleagues via social media. 3) Work efficiency within the organization Institute Personnel are highly efficient in their work. The personnel within the organization can prioritize tasks. Identify defects and take care of work quality. Personnel understand rules and regulations and how to perform their duties well. As a result, the work can be completed on time