More than 90% of students say they are struggling with loneliness, stress, and feeling disconnected, a Sinn Féin survey has found.
The Student Wellbeing Survey found that four out of five students say their college experience is negatively impacting their mental health in the pandemic.
More than 90% reported feeling increasingly lonely, while some 93% of students have found it difficult to stay connected with friends.
The survey of 600 students reveals how many are struggling to receive an education while living and studying in "inappropriate environments".
A number of students say they are living in cramped flatshares with large numbers of other students, or living at home with family members who are working from home and homeschooling.
Some students do not have proper internet connection, laptops, or desks.
Sinn Féin's higher education spokesperson Rose Conway-Walsh said the survey was carried out to establish the link between mental health and the Covid-19 pandemic among third-level students.
Ms Conway-Walsh described the results as "alarming", and said she will present the findings to higher education minister Simon Harris.
The survey also found that three out of four students had found it difficult to communicate with lecturers and other academic staff since the outbreak of Covid-19.
Some 85% of students had struggled to maintain interest and focus in lectures and tutorials, and 70% had struggled to complete assignments and coursework.
A total of 68% of all students are worried about being able to afford to continue in full-time education, the survey also found.