Background: The COVID-19 pandemic has placed enormous strain on health systems around the world, undermining the mental health and wellbeing of healthcare workers. Supporting people with intellectual disabilities may be particularly challenging for workers, as some people with intellectual disabilities may have a limited understanding of the pandemic, and find it challenging to adhere to the restrictions imposed by public health guidelines such as social distancing, lockdowns and change in usual routine and activities. In addition, many people with intellectual disabilities have increased vulnerability to more negative effects of COVID-19, with significantly higher mortality rates. Although there is emerging research on the mental health of healthcare staff during this time, there has been little specific work on the mental health of staff working with people with intellectual disability, particularly a lack of qualitative research. Methods: The current study employed semi-structured interviews with 13 healthcare workers (12 women and 1 man) who were working with people with intellectual disability during the COVID-19 pandemic. The interview data were analysed using thematic content analysis. Findings: The participants spoke in depth about the challenges of the working environment, the impact of providing care during the pandemic on staff mental health, supporting staff mental health and wellbeing and learning for the future. Conclusions: Systematic efforts are required to protect the mental health of this staff cohort, as well as encouraging resilience and successful coping among staff themselves.