Marquis Yamauchi Toyonori (山内豊範, May 12, 1846 – July 13, 1886) was the 16th and final daimyō of Tosa Domain in Shikoku, Japan (modern-day Kōchi Prefecture).

Yamauchi Yōdō continued to wield political power behind-the-scenes, especially after his ban was officially lifted in 1862, and Toyonori's hope of activity was severely limited.

During the Boshin War, he sought a pardon for his father-in-law Uesugi Narinori of Yonezawa Domain.

After the Meiji Restoration and the abolition of the han system in 1871 he was active in Kochi Prefecture in the development of railroads and banks.

His eldest son, Yamauchi Toyokage inherited his title, and served in the Imperial Japanese Army during the Russo-Japanese War and subsequently as a member of the House of Peers