ACLS may refer to:
- Access control list, a list of permissions attached to an object in computer security
- Acrocallosal syndrome, a rare genetic disease
- Advanced Cardiovascular Life Support, a set of clinical interventions for the urgent treatment of cardiac arrest and other life threatening medical emergencies
- Allen Cognitive Level Screen, a leather-lacing test, developed to provide a quick measure of learning/cognitive abilities
- American Council of Learned Societies, a private non-profit federation of scholarly organizations
- Axcelis Technologies, engages in the design, manufacture, and servicing of capital equipment for the semiconductor manufacturing industry