The Communist insurgency in Malaysia, also known as the Second Malayan Emergency, was an armed conflict which occurred in Malaysia from 1968 to 1989, between the Malayan Communist Party (MCP) and Malaysian federal security forces. Following the end of the Malayan Emergency in 1960, the predominantly ethnic Chinese Malayan National Liberation Army, armed wing of the MCP, had retreated to the Malaysian-Thailand border where it had regrouped and retrained for future offensives against the Malaysian government. Hostilities officially re-ignited when the MCP ambushed security forces in Kroh–Betong, in the northern part of Peninsular Malaysia, on 17 June 1968. The conflict also coincided with renewed domestic tensions between ethnic Malays and Chinese in Peninsular Malaysia and regional military tensions due to the Vietnam War.^[89]

The Malayan Communist Party received some support from the People's Republic of China. The support ended when the governments of Malaysia and China established diplomatic relations in June 1974.^[90] In 1970, the MCP experienced a schism which led to the emergence of two breakaway factions: the Communist Party of Malaya/Marxist–Leninist (CPM/ML) and the Communist Party of Malaya/Revolutionary Faction (CPM–RF).^[91] Despite efforts to make the MCP appeal to ethnic Malays, the organisation was dominated by Chinese Malaysians throughout the war.^[90] Instead of declaring a "state of emergency" as the British had done previously, the Malaysian government responded to the insurgency by introducing several policy initiatives including the Security and Development Program (KESBAN), Rukun Tetangga (Neighbourhood Watch), and the RELA Corps (People's Volunteer Group).^[92]

The insurgency ended on 2 December 1989 when the MCP signed a peace accord with the Malaysian government at Hat Yai in southern Thailand. This coincided with the Revolutions of 1989 and the collapse of several prominent communist regimes worldwide.^[93] Besides the fighting on the Malay Peninsula, another communist insurgency also occurred in the Malaysian state of Sarawak in the island of Borneo, which had been incorporated into the Federation of Malaysia on 16 September 1963.^[94]