[Purpose] The purpose of this study was to investigate the effects of the COVID-19 pandemic on mental health in students at university. [Method] 1880 students from university were surveyed. Survey period: July-August 2020 Demographic factors were used department, grade, gender, age. Mental health factors (PHQ-9 Japanese version, GAD-7 Japanese version, IES-R) were used. Decreased motivation to learn, loneliness: Japanese version UCLA loneliness scale was used. [Results] As a result of the survey, in (July-August), 737 patients (123 males and 614 females) were recovered (recovery rate 40.9%). As a result, in terms of gender difference, males had a higher total of "loneliness" than females and had a higher total of PTSD and "invasive symptoms". Students whose parents corresponded to corona had high "anxiety" and "depression". Students who felt rumors had high scores for "PTSD," "depression," "anxiety," and "loneliness." Students "seeking support" also scored higher on PTSD, depression, anxiety, and loneliness. Those who were "not very careful" about infection control were more likely to be depressed than those who were "careful", and those who were "quite careful" were less motivated to learn. Family structure and parental profession have no effect. In addition, the relationship between each psychiatric symptom (PTSD, depression, anxiety disorder) and "loneliness" and "motivation to learn" was examined using covariance structure analysis. When the model was examined, the models of "loneliness" ⇒ "decreased learning motivation" ⇒ "PTSD" ⇒ "depression" and "anxiety" were verified. In other words, it was shown that it is important to deal with "loneliness" to improve mental health and learning motivation during the COVID 19 pandemic. [Conclusion] At the time of the COVID-19 pandemic, college students may be high-risk persons with mental health problems.