Scuffles broke out last night as protestors attempted to break through a police cordon set up on the road to the congress centre in Hanover, where the right-wing party is meeting to elect a new party leadership.
Police also took action after protestors set up illegal road blocks.
Frank Pasemann, an AfD member of the Bundestag, claimed on Twitter a colleague Kay Gottschalk was attacked by 15 “anti-fascist terrorists” as they made their way to the conference centre.
Hanover police spokesman Uwe Lange told a press conference on Friday they were expecting around 8,000 demonstrators.
GettyProtestors on the streets of Hanover ahead of the AfD party congress
1 of 22
Demonstrators scuffle with police during the protest against the anti-immigration party Alternative for Deutschland AfD, after German general election (Bundestagswahl) in Berlin
Mr Lange said the congress centre hosting the AfD event would be ringed with barbed wire and security barriers to protect delegates, with thousands of officers