In the field of second language teaching and learning, researchers have been focusing on the importance of affective analysis, particularly regarding learners' personality types. Recent studies have shown that personality type can have a significant impact on a student's ability to learn a new language. However, little research has been conducted on whether or not personality type has any correlation with the acquisition of second language vocabulary. To delve further into this topic, this study was conducted using questionnaire data from college students. Whether it belongs to any personality trait in the E/I dimension N/S dimension F/T dimension or the J/P dimension, this personality trait is strongly related to the effect of second language vocabulary acquisition. So, personality stereotypes in language learner ability assessment must be broken. Teachers’ personalized teaching capabilities should be improved. In conclusion, this study highlights the importance of considering learners' personality types when designing second language teaching and learning strategies. By understanding how personality type affects language acquisition, teachers can better tailor their approach to meet the individual needs of each student.