The Sound Four (音隠れの忍四人衆, Otogakure no Shinobi Yonin Shū, literally Hidden Sound Shinobi Four People) were Orochimaru's elite bodyguards (Sakon and Ukon are counted as one entity due to their kekkei genkai). Each was given a cursed seal by Orochimaru. They were all defeated and killed by Naruto's friends in the Sasuke Retri arc. Kimimaro Kaguya was a part of the group for a short time, since he was stronger than all four combined, and was intended to be Orochimaru's next host, but an unexpected illness prevented him from participating normally. All five repeatedly make analogies between their opponents and "trash".

The Sound Four were all talented in barrier jutsu. When first seen the four use Four Violet Flames Battle Encampment (四紫炎陣, Shishienjin, English "Four Flames Formation") to create a box-like barrier around the area of Orochimaru's battle, causing anything that touches to burst into flames. To prevent themselves from being attacked and thus bringing down the barrier, the Sound Four created the same barrier around themselves. When the group later fetches Sasuke Uchiha, the four use Four Black Fog Formation Seal (四黒霧陣, Shikokumujin) on him to put him into a coma, preventing his death while his cursed seal advances. When Sasuke is put into a coffin while his seal advances, Sakon puts a seal on the coffin with Black Sealing Method (封黒法印, Fūkoku Hōin) to protect Sasuke from harm. As the group later rests, they set up a Barrier Encampment Method (結界法陣, Kekkai Hōjin) by placing four exploding tags in an array around where they are. When the tags are set, they create an invisible barrier around the area and will detonate should anyone pass the barrier, killing the intruder. Each member of the Sound Four also has a cardinal direction associated with them; this is probably a reference to their positions when performing jutsu as a group.