Ōmori Saneyori served as a bushō during the late Muromachi and Sengoku periods.  He was the head of the Ōmori clan and a retainer of the Ōgigayatsu-Uesugi family.  Saneyori served as the lord of Odawara Castle in Sagami Province. 

Saneyori was born as the eldest son of Ōmori Ujiyori.  His younger brother was Ōmori Fujiyori.

Owing to slander from Ashikaga Masatomo (the Horigoe kubō) and Shibukawa Yoshikane, Ashikaga Yoshimasa (the eighth shōgun of the Muromachi bakufu) suspected Saneyori, and his father, Ujiyori, along with Miura Tokitaka and Chiba Sanetane, to be plotting a rebellion.  Upset at this incident, in the fifth month of 1464, Saneyori went into seclusion.  However, after Ōta Dōkan absconded and efforts by Yoshimasa to persuade him not to depart, Saneyori returned.  Thereafter, he served under Dōkan in battle against Nagao Kageharu, Toyoshima Yasutsune, and Chiba Noritane, but died at a young age.

Under one theory, Saneyori died on 7/16 of Bunmei 15 (1483) and under another theory he died on 10/19 of Bunmei 18 (1486).