Mutual aid may refer to:

• Mutual aid (organization theory), a voluntary reciprocal exchange of resources and services for mutual benefit
• Mutual Aid: A Factor of Evolution, a 1902 collection of anthropological essays by anarchist philosopher Peter Kropotkin
• Mutual aid (emergency services), an agreement between emergency responders
• Mutual aid, an element of social work with groups
• Mutual aid society, an organization formed for the benefit of members
• Billion Dollar Gift and Mutual Aid: Canada's gift of $4 billion to Britain in the Second World War