Basankusu is a town in Équateur Province, Democratic Republic of the Congo. It is the main town and administrative centre of the Basankusu Territory. In 2004, it had an estimated population of 23,764. It has a gravel airstrip, covered and open markets, a hospital, and three cellphone networks, the first of which was installed in 2006. The town is also known as a centre for bonobo conservation efforts. Despite such developments, most inhabitants live at a subsistence level: hunting, fishing, keeping chickens and keeping a vegetable plot. In 2010, the workers at the local palm plantation would earn an average monthly salary of $40 (US dollars), most others would have much less.

The location of the town on the Lulonga River, a tributary of the Congo, at the confluence of the Lopori and Maringa Rivers has contributed to its success as a centre for trade in the region. Set deep in tropical rainforest, the rivers serve as the highways for transport of people as well as goods.

Historically, Basankusu holds some stories of exploitation during the times of the Abir Congo Company but was also the gateway to much of Equateur Province for those individuals involved in the reforms which came from the Casement Report and the Berlin Conference of 1884-85.

The name Basankusu is said to have been misunderstood by its European explorers and colonisers, who lacked knowledge of the local language. The Mongo group that founded Basankusu were the Okutsu; their descendants were called the Basaa Okutsu, meaning the "children of the Okutsu". This name was contracted slightly into the name Basaa'kutsu.

Another account of the etymology of Basankusu is that it comes from basa ba nkoso, meaning "quarrelling parrots", or possibly Baasa bankoso, "small parrots".

Basankusu was the first trading post of the Abir Congo Company (ABIR) along the Congo River from Kinshasa (then known as Leopoldville), the capital of the Congo. Later known as the Compagnie du Congo Belge, the Abir Congo Company harvested natural rubber in the 19th and early 20th century. It was granted a large concession with the rights to tax the inhabitants, taken in the form of rubber. The collection system revolved around a series of trading posts along the two main rivers in the concession – the Lopori and the Maringa. Each post was commanded by a European agent and manned with armed sentries to enforce taxation and punish any rebels.

ABIR would sell a kilogram of rubber in Europe for up to 10 francs (fr), which cost them only 1.35 fr to collect and transport. However, this came at a cost to the human rights of those who could not pay the tax, with imprisonment, flogging, and other corporal punishments recorded.

The Casement Report comprises a multitude of individual statements gathered by the British Consul, Roger Casement, including several detailing the grim tales of killings, mutilation, kidnapping, and cruel beatings of the native population by soldiers of the Congo administration of King Leopold. The British Parliament demanded a second meeting of the 14 signatory powers of the 1885 Berlin Conference, at which time the Belgian Parliament forced a reluctant Leopold to set up an independent commission of enquiry. This led to the arrest and punishment of several officials who had been responsible for murders during a rubber-collection expedition in 1903. The reforms that followed the Casement Report, including those that concerned ABIR at Basankusu, set the foundation for the colonial Belgian state of Congo.