American Society for the Prevention of Cruelty to Animals (usually referred to as the ASPCA) is a non-profit organization dedicated to preventing the abuse of animals. It was founded by Henry Bergh on April 10, 1866. It is the oldest humane organization in the United States. Their mission is "to provide effective means for the prevention of cruelty to animals throughout the United States".

The ASPCA works primarily with companion animal issues, such as pet care, equine or horse cruelty issues, and animal cruelty and neglect. Their programs and services include: a national poison control hotline for pet owners and animal health professionals; a shelter outreach program to promote best practices within locally-owned shelters, a corporate partner program to promote animal-friendly products and services, and a special anti-cruelty initiative to teach humane education and humane law enforcement practices across the United States. In New York State, the ASPCA's Humane Law Enforcement division has powers to investigate cruelty and enforce laws. The Humane Law Enforcement division has been featured on the television program Animal Precinct.

Additionally, the ASPCA provides relief services for the domestic animal victims of natural disasters such as Hurricane Katrina, where the National Outreach department collected donations to provide supplies; coordinated volunteer efforts; deployed rescue teams to recover abandoned pets; provided temporary shelter to displaced animals; and reunited pets with their owners.
The ASPCA is very active in lobbying for humane legislation, with regional and federal lobbyists covering all 50 states. The ASPCA communicates with federal and state legislators to consider animal-friendly legislation and bills. The ASPCA also drafts humane legislation initiatives and proposals for legislators to consider during their sessions. The ASPCA's "Advocacy Brigade" allows users to write/e-mail their legislators on important animal legislation bills and referendums.

Many local organizations use the term SPCA, but they are not related to the ASPCA, which is based in New York and has a national reach. Local organizations take in animals that are stray, abused, or owner give ups. They may be private, or contracted with their local government.