Healthcare students play an important role in volunteering activity, often addressing staff shortages. However, during the COVID-19 pandemic, the willingness of students to volunteer in contribution to the pandemic response, especially in Vietnam, has not been thoroughly investigated. This study aimed to determine the prevalence of and factors associated with the willingness of healthcare students to volunteer during the COVID-19 pandemic in Vietnam. For this, an online cross-sectional survey was conducted, between June 7th and July 6th, 2021, among healthcare students from 10 fields of study at the largest public university of medicine and pharmacy in the Mekong Delta, Vietnam. Of 2032 respondents, 1473 (72.5%) reported that they would be willing to volunteer during the COVID-19 pandemic. More than half of the students reported having a desire to volunteer in non-patient contact activities such as data entry (65.9%) and logistics (57.7%). Whereas less than 50% of the participants were willing to volunteer with activities involving patients. Year of education, study field, educational format, living arrangements, health status self-perception, chronic illness possession, COVID-19 fear level, past volunteering experience in non-healthcare sectors, and COVID-19 prevention and control training course attendance were all associated with a willingness to volunteer. The strongest barriers preventing volunteering included fear for the health of their family and lack of training/knowledge. Conclusively, healthcare students reported a high level of willingness, indicating a positive attitude toward responding to the COVID-19 pandemic. Adequate training should be employed to increase the willingness among healthcare students in Vietnam.