The move also marked a major shift on a problem that has grown from an environmental issue into a security threat.
A UN Security Council resolution that renewed an arms embargo, travel bans and asset freezes against armed groups in Congo now includes individuals who support those groups "through illicit trade of natural resources, including gold or wildlife as well as wildlife products".
The Security Council passed the resolution two days after including similar language in a sanctions regime imposed on armed groups in the Central African Republic.
Conservation group WWF said the resolutions "represent the first times that the UN Security Council has specifically named illicit trade of wildlife and wildlife products in sanctions regimes".
It follows years of warnings from advocates and UN officials that wildlife trafficking, particularly elephant ivory, has increasingly become a source of financing for armed groups.
Wendy Elliott, WWF species programme manager, said: "It's a huge step forward."