Naitō Torajirō (内藤 虎二郎; 1866-1934), commonly known as a pseudonym Naitō Konan (内藤 湖南), was a Japanese historian.

He was born in what is now Akita prefecture. He distinguished himself as a journalist. In 1907 he found Manwen Laotang 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.