Frits Clausen (12 November 1893 – 5 December 1947) was a far-right Danish politician and leader of the National Socialist Workers' Party of Denmark (DNSAP) before and during World War II.

After the war, Clausen studied medicine in Heidelberg and became a doctor in 1924, after which he returned to Aabenraa, which had been voted back to Denmark in 1920, and set up a practice.

Under Clausen's direction, the party essentially espoused nationalism and called for a stronger relationship between Denmark and Nazi Germany.

After the elections, Clausen joined the German Army and saw active service on the Eastern Front as a surgeon, although he did not resign his position as chief of the DNSAP.

Clausen's failure in the elections and his unwillingness to actively assist in forming a Danish branch of the Schutzstaffel alienated his German supporters.