To help students improve their English teaching and learning strategies and their learning outcomes, it is crucial to be aware of some common errors they make. The purpose of this study was to determine the kinds of errors made by students in writing descriptive texts, and to find out the most dominant error made by students in writing descriptive texts. The research method used is descriptive quantitative. This research was conducted in one of the private junior high schools in South Cilacap with a population of 134 students consisting of class VII which is divided into 6 classes. Researchers used simple random sampling with a total sample of 24 students. The written test instrument was used in this study. The results showed that there were four kinds of errors in writing. There were 31 or 38% items students‟ error in omission, 20 or 24% in misformation, 15 or 18% in addition, then 16 or 12% in misordering. Then, the students‟ most dominant error is omission with 31 or 38%.