Rasmus Paludan, head of Denmark's far-right Stram Kurs (Hard Line) party, has been given a month in jail for a string of offences including racism.
He was convicted of posting anti-Islam videos on his party's social media channels.
Paludan was given a suspended jail term for racism in 2019 and the court heard that influenced the latest verdict.
He will appeal against his sentence, which includes a two-month suspended jail term.
He faced 14 charges, including racism, defamation and dangerous driving.
Paludan, 38, was disbarred for three years as a criminal lawyer and banned from driving for a year.
Stram Kurs won 1.8% of the vote in national elections in 2019, falling just short of the 2% threshold needed to enter parliament.
It ran on a platform of banning Islam and deporting all of Denmark's Muslims. Paludan has himself led demonstrations that involve burning the Koran in areas with ethnic minority communities.
In videos posted online Paludan made derogatory comments about Muslims, but argued he had not made the videos himself. He has also insisted he was upholding Denmark's tradition of free speech.
The court found him guilty of defaming a woman of Somali origin at a demonstration by insinuating she was a prostitute, Danish media report.
He was not in court in the town of Naestved to hear the verdict.