Latinxua Sinwenz (拉丁化新文字; also known as "Sin Wenz", "Latinxua Sinwenz", "Zhongguo Latinxua Sin Wenz", "Beifangxua Latinxua Sin Wenz" or "Latinxua") is a little-used romanization system for Mandarin Chinese. It was usually written without tones under the assumption that the proper tones could be understood from context.

Sin Wenz was developed in the 1920s by Qu Qiubai (1899-1935) in collaboration with two Russian linguists, V.S. Kolokolov (1896-1979) and A.A. Dragunov. The system was further improved in the early 1930s by the Oriental Institute of the Academy of Sciences in Leningrad.

The system was primarily used in the Soviet Union, though figures such as Lu Xun supported its use in China. Its use was not widespread. The system was opposed by the Kuomintang.