Language errors that occur are usually caused by a lack of mastery of Indonesian grammar, linguistic units, the meaning of word formation, and still being influenced by the mother tongue or first language. This research aims to describe errors in sentence usage based on a study of syntax in foreign students' academic texts at Jambi University and to describe the obstacles faced by foreign students in writing academic texts. This research was carried out at the Indonesian Language and Literature Education Study Program, Jambi University, the research subjects were foreign students from Thailand. The approach used is a content analysis approach. The sampling technique uses purposive sampling technique. Data collection uses two techniques, namely assignments and interviews. The data analysis technique used follows the content analysis steps. Test the validity of the data in this research using theory triangulation and source triangulation. The research results show that errors in the form of ambiguous sentences are often the errors that most often appear in foreign students' academic texts. From the results of the interviews conducted, it was found that the obstacles faced by foreign students in writing academic texts in Indonesian were because the systematics of writing in Indonesian were different from Thai, apart from that their mastery of vocabulary and understanding of the meaning of words was still minimal.