Teacher absenteeism significantly impacts student achievement in the EFL acquisition process, as it is a strong predictor of exam scores and has a direct negative impact on learning. Previous studies have shown that teacher absenteeism leads to low exam scores, disrupting the learning process and thwarting psychological enthusiasm. This paper aims to understand the impact of teacher absenteeism on student achievement in EFL classes in the Algerian LMD system through questionnaires submitted to both teachers and students. The results show that teacher absenteeism significantly disrupts the EFL acquisition process, resulting in lower scores and poor performance compared to regular achievements of students. Students are highly disillusioned, and rigorous measures should be taken against this prevalence to improve student outcomes.