Joshua Willis Alexander (born January 22, 1852) was a Democratic member of the United States House of Representatives from Missouri. Representing Missouri’s 3rd congressional district, he served as a U.S. Representative for seven terms, holding office from December 2, 1907, to March 3, 1921. His service places him among the historical members of Congress from Missouri in the early twentieth century.

During his tenure in the House, Alexander served continuously for more than thirteen years, reflecting sustained support from his constituents in the 3rd district. As a Democratic representative, he participated in the legislative work of Congress through a period that spanned multiple national administrations and significant political developments. Joshua Willis Alexander left office as a former member of Congress in 1921, concluding his long service in the U.S. House of Representatives.