Lawrence Kalter Roos (February 1, 1918 – September 23, 2005) was an American banker and Republican from Missouri, United States.

After World War II, he worked in St. Louis for an advertising and public relations firm.

[2] Roos was first elected to public office in 1946, serving two terms (1947–1951) in the Missouri House of Representatives.

Although he won the Republican primary easily,[3] he lost the general election to the incumbent governor, Warren E. Hearnes, by a margin of 61–39%.

[6] Roos died from stomach cancer in Barnes-Jewish Hospital in St. Louis on September 23, 2005, at the age of 87.