Access to vaccinations is crucial for everyone in the fight against the COVID-19 pandemic, regardless of migration or refugee status. This study explored COVID-19 prevention knowledge, attitudes, and vaccination challenges among refugees and irregular migrants from Myanmar in Malaysia. This study employed a descriptive mixed-method approach. Convenience sampling was used to conduct an online survey of 174 participants and two focus groups (N = 14). The majority (51.7 %) were refugees, and 48% were irregular migrant workers. In this study, 90.9% of the participants used social networks and social media chats to obtain information about COVID-19, 84.1% understood and found the vaccination campaign helpful, and 44.2% were aware of it. Although 70% of the participants considered vaccination crucial, 95% said that they would not take it because of fear of arrest and deportation, even though they considered vaccination necessary. Approximately 21.2% of the workers reported that their employers did not provide masks or hand sanitisers. Most of the participants (39.7 %) lived in dormitories provided by their employers. This puts them at a higher risk of infection because of the difficulty in practising social distancing. As part of COVID-19 prevention, the government should grant an amnesty period and work with migrant civil society organisations to administer vaccinations and effective measures for all immigrant populations in Malaysia.