Born in Topeka, Kansas, Roberts is a graduate of Kansas State University. He served as a captain in the U.S. Marine Corps and worked as a newspaper reporter before entering politics in the late 1960s. He was elected to the U.S. House of Representatives in 1980 to succeed 1st District Congressman Keith Sebelius, for whom he had worked. He served eight terms in the House, including one as chairman of the House Agriculture Committee.
Roberts was elected to the U.S. Senate in 1996, and is currently serving his third term. He has a conservative voting record. On the Intelligence Committee he was responsible for an investigation into the intelligence failures prior to the 2003 invasion of Iraq. He led the creation of the Pat Roberts Intelligence Scholars Program in 2004.