Tobi (ƒgƒr, Tobi) is a former subordinate of Zetsu. After Sasori's death, Tobi takes his ring, position, and partner (Deidara) in Akatsuki, thereby becoming a full member. After Deidara's death, Tobi is shown giving Pein, the leader of Akatsuki, orders, and he refers to himself as Madara Uchiha. Tobi's personality is at odds with the standard amongst Akatsuki members; while most are dedicated and serious, Tobi is more carefree and goofy. These personality traits tend to irritate Deidara, who often attacks Tobi in some way when Tobi unintentionally annoys him. Kisame Hoshigaki, on the other hand, appreciates Tobi's ability to brighten up their gloomy organization. Prior to revealing himself as Madara Uchiha, Tobi uses a very formal and correct manner of speech. As Madara, his personality and speech are completely different, as he speaks much less formally and is more serious and arrogant.

Tobi's actual appearance remains a complete mystery. He wears an odd mask that covers his entire face save for his right eye, which like other Uchiha has the Sharingan. He also has several bolts or pins present on the arms of his uniform, now obscured by his Akatsuki cloak. Furthermore, Tobi does not wear a visible headband, though his Uchiha name would suggest that he originates from Konohagakure. His fighting style is equally shrouded in mystery, as his only notable trait is the ability to recover from what are presumably debilitating or fatal blows without injury and in a matter of seconds. Despite this lack of definitive details, Zetsu refers to Tobi as a "good boy", implying that he is relatively young