The active and illegal foreign armed groups operating on the soil of the DR Congo include the following:

The Democratic Forces for the Liberation of Rwanda (FDLR) is the largest illegal foreign armed group operating in the DR Congo. While there is currently a growing number of Congolese among their ranks, the group is primarily formed from members of the Rwandan government and army ousted in 1994 as well as Rwandan refugees. Its public purpose is to use military pressure to open "inter-Rwandan dialogue" with the current Rwandan government, but its covert purpose appears to be to overthrow the Rwandan government. The FDLR currently operates in eastern DR Congo and Katanga province. Its current strength is estimated to be 2000 combatants. It can be recalled that in 2009, a joint operation was mounted against the FDLR by FARDC, the Rwandan Army (RDF), and MONUSCO.

The Allied Democratic Forces (ADF) is a Ugandan rebel group based along the Rwenzori Mountains of eastern DR Congo. Most of its members are Islamists who want to establish Shari'a law in Uganda. The ADF was formed around 1998 by a merger of various streams of discontented sectors of Ugandan society which felt alienated after the overthrow of Idi Amin. The group appears to be receiving external funding from unknown sources. In June 2010, the FARDC launched an attack called “operation Ruwenzori” against the ADF. The ADF currently number approximately 500 combatants but the high level of secrecy in the organization and its compartmentalized structure make it difficult to ascertain its overall strength. Since 2001, the Uganda government offered Amnesty and Reinsertion program to all members of the ADF.

The Lord's Resistance Army (LRA) is a Ugandan rebel group currently based along the northern border areas of Congo as well as in the eastern Central African Republic. The LRA was created in 1997 by remnants of the Ugandan spiritual rebel movement under Alice Lakwena and the remnants of the Ugandan army overthrown by President Yuweri Museveni. The group was formed primarily by individuals from the Acholi tribe in Northern Uganda. Between 1994 and 2004, the LRA was based in Southern Sudan but after the peace negotiations that led to the Sudan People’s Liberation Army (SPLA) taking over control of Southern Sudan the group moved its base to DRC. This was in September 2005. The LRA remained relatively quiet in the DRC until it began a violent expansion campaign in September 2008. This campaign forced the armies of the DRC, Uganda and the SPLA IN Southern Sudan to launch a joint military operation against them in December 2008. The LRA is made up of hard core Ugandan combatants as well as recruits forcefully abducted from the DRC, South Sudan and the Central African Republic.

The National Liberation Forces (FNL) is a Burundian rebel group originally formed in 1985 as the military wing of a Hutu-led rebel group called the PALIPEHUTU. Both the PALIPEHUTU and the FNL signed a peace agreement in September 2006 and became simply FNL. While most of the FNL integrated into the national Burundian army after the elections in mid 2010 the remnants restarted rebel activities. They later started infiltrating the Ruzizi plains and Lake Tanganyika and crossed into South Kivu where they created rear bases to fight the Burundian armed forces. The FNL currently appears to be in an alliance with Mai Mai Yakutumba and FDLR in South Kivu.

Since 2002 to July 2013, the DDRRR Section repatriated more than 29,000 foreign ex-combatants and their dependants. The Section has 18 sites in North Kivu, South Kivu, Oriental Province and North Katanga. It also runs four rapid response mobile teams capable of a rapid responding for any emergency throughout their operational areas. The DDRRR Section has visible presence in most parts of eastern DR Congo and that enables it to facilitate the transportation of Rwandan refugees thereby complimenting the work of the United nations High Commission for Refugees, (UNHCR.)