Many educational institutions have fully implemented online learning during the 2020 school year due to the COVID-19 pandemic. This path is taken to anticipate the spread of the COVID-19 pandemic that is currently affecting the world. The significant change in the learning model drives students to make some adjustments. This situation needs reviewing to see the indication of the effects that may arise as a result of online learning. This research aims to measure those possible indications, such as mental workload, stress level, and learning motivation and their effects on learning achievements. For this research, the focus is on students of a university in Surabaya. Based on an initial questionnaire distributed, 50% of the respondents stated that the delivery of material through online learning is considered less effective and that 66% of the respondents stated that online learning affects their stress level. This measurement seeks to give an overview that will help educational institutions better develop online learning methods for future terms. The methods used to measure these indications are the DRAWS method for mental workload measurement, stress level measurement using The Student-life Stress Inventory, and Motivated Strategies for Learning Questionnaire (MSLQ) for learning measuring motivation level. Based on the research conducted through 357 respondents, the result shows that 78.43% of students felt an increase in their academic performance from online learning, 7.56% felt no significant change, and 14.01% felt a decrease. It was obtained that the motivational variable and academic stress significantly affects the students’ academic performance and that mental workload did not affect academic performance significantly.