Colonel H.H. Prince Yi Geon (October 28, 1909 – December 21, 1990), also Ri Ken and , was a Korean prince and a cavalry officer in the Imperial Japanese Army during the Second World War. The first son of Prince Yi Kang of Korea by Lady Jeong, he was a grandson of Emperor Gwangmu. His Korean name was Yi Geon ( I Geon), and his birth name was Yonggil ( Yonggil). He was brought to Japan in 1918, and entered Gakushūin Primary School. He married , a maternal cousin of Crown Princess Bangja, on October 5, 1931, in Tokyo.