The aim of this research paper is to investigate how the English knowledge of undergraduates impact when pursuing a degree in English medium specially for computer science students. To conduct this experiment, first utilize the data samples from Trincomalee eastern university of Sri Lanka with the computer science department. Through the experiment, it was identified that there is a measurable impact on semester success for the undergraduates when academic studies are educated by the English language. This influence highly impacted the first-year students but still existed in some students by the second and third year. However, the important thing is prior knowledge in English, highly impacts to pursue a merit pass and benefitable scholarships. But it should be noted, studying an English medium degree in computer science is fascinating to pursue international achievements and English medium instructions are highly impactful to pass the first degree of the university students.

Keywords : Impact, semester success, English instruction, eastern university.