Matasaburō Watanabe (渡辺 又三郎 Watanabe Matasaburō; 1850–1910) was a Japanese politician who served as the Mayor of Hiroshima from 9 September 1909 to 3 July 1910.
Watanabe lived in Hiroshima Prefecture and served as Vice President of the Hiroshima Lawyers' Club. He was also among the owners of Chugoku Shimbun.
Further reading Andrew Fraser, R.H.P. Mason and Philip Mitchell, Japan's Early Parliaments 1890-1905: Structure, Issues and Trends (London & New York, 1995)