Naitō Torajirō (内籐 虎次郎 Naitō Torajirō; August 27, 1866–June 26, 1934), commonly known as Naitō Konan (内藤 湖南 Naitō Konan), was a Japanese historian and Sinologist. He was the founder of the Kyoto School of historiography, and along with Shiratori Kurakichi (the founder of the Tokyo School), was one of the leading Japanese historians of East Asia in the early twentieth century. His most well-known book is called Nara.
He was born in what is today Akita Prefecture. He distinguished himself as a journalist. In 1907 he found Manwen Laodang in Mukden. As an authority of Chinese history, he was invited to Kyoto Imperial University by Kano Kokichi in 1907 and got involved in the foundation of the Department of Oriental History.
Naitō's most influential contribution to historiography was the recognition and analysis of the Tang-Song transition as an important watershed. He argued that the social, political, demographic and economic changes that occurred between the mid-Tang Dynasty and early Song Dynasty represented the transition between the medieval (chūsei) and early modern (kinsei) periods of Chinese history.