Simple present tense is part of the basic tense that must be mastered by students in learning English if students do not fully understand the simple present tense material, it can result in the achievement of learning outcomes. present tense and the most dominant difficulties experienced by students in understanding the simple present tense. This study uses a qualitative descriptive method which aims to determine the difficulties of students in understanding the simple present tense and to find out the most dominant difficulties experienced by students of class X marketing at SMKN 2 Kotabumi. The data collection in this study was a questionnaire as the main data and follow-up interviews as supporting data. There are 8 students who are the object of research in data collection for marketing students in class X. The results showed that there were 4 aspects of students' difficulties in understanding the simple present tense, including concepts, functions, patterns, and time signals of the simple present tense. The most dominant difficulty experienced by students in understanding the simple present tense is the pattern, many students sometimes make mistakes in making sentences, compiling simple present tense sentences and sometimes greeting students using tobe, verbs in sentence patterns.