The internal conflict in Peru is an armed conflict between the Government of Peru and the Maoist guerrilla group Shining Path. The conflict's main phase began on 17 May 1980 and ended in December 2000. From 1982 to 1997 the Túpac Amaru Revolutionary Movement (MRTA) waged its own insurgency as a Marxist–Leninist rival to the Shining Path.

As fighting intensified in the 1980s, Peru had one of the worst human rights records in the Western Hemisphere and experienced thousands of forced disappearances while both the Peruvian Armed Forces and Shining Path acted with impunity, sometimes massacring entire villages. 50,000 to 70,000 people were killed, making it the bloodiest war in the country's independent history. This includes many civilians who were deliberately targeted by all factions. The Indigenous peoples were disproportionately targeted, with 75% of those killed speaking Quechua as their native language.

Since 2000, the number of deaths has dropped significantly and recently the conflict has become somewhat dormant. The conflict is also characterized by serious violations of human rights.

The first guerrilla outbreaks arose in Peru in the early 1960s, during the Moderate Civil Reform, when the Revolutionary Left Movement (MIR), a guerrilla group founded and led by Luis de la Puente Uceda, began its first attacks against the Peruvian State in 1962. However, despite their training in Fidel Castro's Cuba, the members of the MIR often were in an unstable state, as they were often based in the Amazon. As a result, its members were easily killed by the police and the armed forces. During these counterattacks, their leader and founder was killed and the group eventually would collapse completely by 1965. Another guerrilla group that also emerged simultaneously was the National Liberation Army (ELN) led by Juan Pablo Chang Navarro and trained by Cuba. It was made up of some former members of the MIR and other people who were recruited. However, this organization suffered the same fate as the MIR since many of its members were infected with leishmaniasis. As a result, the armed forces killed its members. The ELN received military training in Cuba and operated from 1962 to 1965. After its dismantling, its main leaders fled to Bolivia where they would fight alongside Che Guevara in the Ñancahuazú Guerrilla, where they would be assassinated while trying to establish a guerrilla focus in the Andes.

Prior to the conflict, Peru had undergone a series of coups with frequent switches between political parties and ideologies. On 2 October 1968, General Juan Velasco Alvarado staged a military coup and became Peru's 56th president under the administration of the Revolutionary Government of the Armed Forces, left-leaning military dictatorship.^{[citation needed]} Following a period of widespread poverty and unemployment, Velasco himself was overthrown in a bloodless military coup on 29 August 1975. He was replaced by Francisco Morales Bermúdez as the new President of Peru.

Morales announced that his rule would provide a "Second Phase" to the previous administration, which would bring political and economic reforms. However, he was unsuccessful in delivering these promises, and in 1978, a Constitutional Assembly was created to replace Peru's 1933 Constitution. Morales then proclaimed that national elections would be held by 1980. Elections were held for the Constituent Assembly on 18 June 1978, whilst martial law was imposed on 6 January 1979. The Assembly approved the new constitution in July 1979. On 18 May 1980, Fernando Belaúnde Terry was elected president. Between February 1966 and July 1980 approximately 500 people died of political violence.

Many affiliated with Peru's Communist Party had opposed the creation of the new constitution and formed the extremist organization known as the Communist Party of Peru – Shining Path. This ultimately led to the emergence of internal conflict, with the first attacks taking place a day before the elections. Despite this, national elections continued and Fernando Belaúnde was elected as the 58th President of Peru in 1980. Belaúnde had already served as the country's 55th president prior to Velasco's coup in 1968.^{[citation needed]}

During the governments of Velasco and Morales, the Shining Path had been organized as a Maoist political group formed in 1970 by Abimael Guzmán, a communist professor of philosophy at the San Cristóbal of Huamanga University. Guzmán had been inspired by the Chinese Cultural Revolution which he had witnessed first-hand during a trip to China. Shining Path members engaged in street fights with members of other political groups and painted graffiti encouraging an "armed struggle" against the Peruvian state.