This paper aims to discuss ASEAN’s conflict resolution preference by employing the Responsibility to Protect (R2P) to prevent a number of casualties in intra-state conflict taking place in Southeast Asia. Established by the United Nations in 2005, the Responsibility to Protect is immediate international community response to particularly save unarmed civilians from four crimes: genocide, war crime, crime against humanity and ethnic cleansing, which it is included into term of Mass Atrocity Crimes. R2P has three main ideas: 1) protecting population from genocide, war crime, crime against humanity and ethnic cleansing is responsibility of a state; 2) assisting the fulfillment of state’s primary responsibility to protect becomes responsibility of the international community; 3) the state’s failure to assure security of its people from four crimes allows the international community to coercively interfere, which is from economic sanction to military intervention. R2P has extensively developed treatments beyond merely security approach compared to the humanitarian interventions, which are 1) the responsibility to prevent, 2) the responsibility to react and 3) the responsibility to rebuild. In Southeast Asia, human security problem remains high concerning state violence to minority groups, political injustice of power abuse and human rights issues of citizen. In this regard, most women and children have used to suffer from the intra-state crisis. Hence, ASEAN needs to take R2P into account to reduce large number of victims. Although peace talk is important instrument of peace process as implemented by ASEAN up to now, gradual intervention as mentioned in R2P treatments is more effective to ensure human security during the crisis. In addition, implementing R2P requires a serious commitment of ASEAN leaders to reconstruct a body of this association.