This article analyzes the impact of internal control on the performance of pharmaceutical companies, providing additional empirical evidence on the effects of internal control on performance. The research method used includes surveys through questionnaires distributed among pharmaceutical companies to assess internal control and each element of internal control of these firms. Quantitative research was carried out with SPSS 25 software. The results show that monitoring, information and communication are the factors that have the strongest impacts on the performance of pharmaceutical companies. This can be explained that, for pharmaceutical companies, good monitoring and information and good tradition will positively affect the effectiveness of internal control in particular and the performance of the business. Based on the research results, the author proposes some recommendations to improve the effectiveness of internal control, thereby contributing to improve the performance of pharmaceutical enterprises.