This study evaluated college students' mental fatigue between traditional face-to-face classes and online learning. Due to the coronavirus that started in the Philippines last March 2020, the students faced a fast transition to online learning. The teachers and students had a significant adjustment to that setup which affected the student's mental health, particularly mental fatigue. The researchers would like to assess and compare the mental fatigue of students between traditional and online learning; the researchers conducted a digital survey on the students with 100 respondents where 51% are females, and 49% are males. The Mental fatigue questionnaire was used, and it was reported that 86% of students experience mental fatigue online and 74% in traditional. The ANOVA results for the comparison of both modalities showed that in an online setup, students are more prone to mental fatigue, with a mean of 18.825 and 16.010 for a traditional setup. This study found that the only significant factor is the duration of study in an online class, and no factor was found to be significant in a traditional setup.