Asakura Kagetoyo served as a retainer of the Asakura clan in Echizen Province.

Kagetoyo was the only son of Asakura Kagefuyu.  Following the death of this father in 1495, Kagetoyo inherited the role of gunji, or governor, for the Tsuruga District. Kagetoyo’s sisters were married to clan members including Asakura Norikage (Sōteki),  Horie Kagezane, Toba Kagetomi, and 青蓮華 with the Court title of Governor of Ōmi.  Asakura Kagefusa, his father-in-law,  had fled from Echizen to Kyōto after an incident whereby Kagefusa killed his younger half-brother, Norikage, in a sumō event.  This owed to Kagefusa’s resentment from being a rank below Norikage in terms of seniority in the clan owing to the fact that Norikage was born to his father’s formal wife whereas Kagefusa was born to a mistress.  In Kyōto, Kagefusa served Hosokawa Masamoto, the kanrei, or deputy shōgun.  Kagefusa disclosed to Kagetoyo a plot for a rebellion.  This involved leveraging his brother-in-laws to overthrow Sadakage, lord of the clan. Kagetoyo consented.

While Kagefusa led an army from Ōmi into Echizen, Kagetoyo and the co-conspirators were expected to launch the rebellion from within Echizen, but none of the brother-in-laws followed through with the plan, while Sōteki secretly informed Sadakage of the rebellion.  Sadakage then led several thousand mounted soldiers to Tsuruga and surrounded Kagetoyo in his base at Tsuruga Castle.  Kagefusa and his men did not arrive in time to counter Sadakage.  Following attempts to defend the grounds, Kagetoyo killed himself, leaving two infant sons behind for rescue.