Tadayoshi Nagashima (長島 忠美 Nagashima Tadayoshi, born January 9, 1951) is a Japanese politician, serving in the House of Representatives in the Diet (national legislature) as a member of the Liberal Democratic Party. A native of Yamakoshi, Niigata and graduate of the Toyo University he was elected to the Diet for the first time in 2005 after serving as mayor of his hometown Yamakoshi.