The purpose of this research was to study factors affecting stress of online learning due to the COVID-19 situation at the Faculty of Education, Thailand National Sport University Chonburi Campus, and to create equations to predict the stress of students. The samples consisted of 280 students in the Faculty of Education, Thailand National Sport University Chonburi Campus. The research instruments were the Suanprung Stress Test and a questionnaire gauging emotional and mental status, perceived severity of stress, opportunity for risk of stress, perceived usefulness of stress management, university policies that promote stress management, environment, and social support. The data were analyzed in terms of frequency, percentage, mean, standard deviation and Stepwise Multiple Regression Analysis. The results indicated that 1) study stress levels during the COVID-19 situation were at a moderate level: subjects had a mild level of stress 8.93 percent, moderate level of stress 56.78 percent, high level of stress 33.93 percent and severe level of stress 0.36 percent; 2) The subjects’ emotional and mental well-being, perceived severity of stress, perceived usefulness of stress management, University policies that promote stress management, environment, social support were at a high level, and Opportunity for risk of stress moderate level. 3) The factors that related to the stress of online learning due to the COVID-19 situation comprised were 4 variables: achievement perceived usefulness of stress management, opportunity for risk of stress, university policies that promote stress management, and social support. There was a statistically significantly difference at the 0.1 level. These 4 factors could predict the Stress about percentage of 70.50. The significantly predicted equations were as follows: In term of raw scores: Y/ = 75.425 + (-5.180) (X4) + 3.816 (X3) + (-3.465) (X5) + (-2.689) (X7) In term of standard scores: Z / Y = (-0.324) (Z X 4) + 0.280 (Z X 3) + (-0.225) (Z X3) + (-0.165) Z X 7)