The insurgency in Aceh, officially designated the Rebellion in Aceh (Indonesian: Pemberontakan di Aceh) by the Indonesian government, was a conflict fought by the Free Aceh Movement (GAM) between 1976 and 2005, with the goal of making the province of Aceh independent from Indonesia. The aftermath of a strong military offensive in 2003 and the 2004 Indian Ocean earthquake brought a peace agreement and an end to the insurgency.

The Free Aceh Movement (Indonesian: Gerakan Aceh Merdeka, GAM; Acehnese: Geurakan Acèh Meurdèka / Gěrakan Aceh Měrdeka) was a separatist group seeking independence for the Aceh region of Sumatra, Indonesia. GAM fought against Indonesian government forces in the Aceh insurgency from 1976 to 2005, during which over 15,000 lives are believed to have been lost.The organisation surrendered its separatist intentions and dissolved its armed wing following 2005 peace agreement with the Indonesian government, and subsequently changed its name into Aceh Transition Committee (Indonesian: Komite Peralihan Aceh, KPA). The Indonesian government called the group the Aceh Security Disturbance Movement.