The COVID-19 pandemic is having a profound effect on all aspects of society, including mental health as well as physical health. We explore the psychological, social and neuroscience impacts of COVID-19, and set out immediate priorities and longer-term strategies for mental health science research. These priorities were informed by surveys of the public and an expert panel convened by the UK Academy of Medical Sciences and the mental health research charity, MQ: Transforming Mental Health, in the first weeks of the pandemic in the UK in March 2020. We urge UK research funding agencies to work with researchers, people with lived experience and others to establish a high level co-ordination group to ensure that these research priorities are addressed, and to allow new ones to be identified over time. The need to maintain high quality research standards is imperative. International collaboration and a global perspective will be beneficial. An immediate priority is collecting data on the mental health impacts of the COVID-19 pandemic across the whole population and vulnerable groups, and on brain function, cognition and mental health for COVID-19 patients. There is an urgent need for research to address how mental health consequences for vulnerable groups can be mitigated under pandemic conditions, as well as on the impact of repeated media consumption and health messaging around COVID-19. Discovery, evaluation and refinement of mechanistically-driven interventions to address the psychological, social and neuroscientific aspects of this pandemic are required. Rising to this challenge will require integration across disciplines and sectors, and should be done together with people with lived experience. New funding will be required to meet these priorities, but it can be efficiently leveraged by the UK’s world-leading infrastructure.