This comes just two months after the controversial right-wing Akademikerball was held in the Hofburg - the ball is a known gathering place for right-wing politicians and nationalist student fraternity members and is supported by the Freedom Party.
Wilders and Strache will hold a press conference in the afternoon, and an evening panel discussion will take place at 6:30pm in the Hofburg. Only participants who have previously registered and have official ID can attend.
Vienna's Socialist Youth group and the left-wing activist group Offensive gegen Rechts have said they will hold a protest rally on Heldenplatz at 5:00pm. Natascha Strobl, from Offensive gegen Rechts, told Der Standard newspaper that around 200 people had said they would join the rally.
Strobl said that it was important to "get racism out of the Hofburg". "Once again the FPÖ is meeting there with the extreme right, and those who run the Hofburg do not hesitate to offer them this big stage," she added.
Human rights organization SOS Mitmensch has organised a flash mob at 6pm on Josefsplatz, in front of the Hofburg, against what it says is "propaganda against Muslims". Organisers expect around 50 participants.
Police spokesman Thomas Keiblinger said that the areas around the Hofburg would not be locked down, as they were for the Akademikerball. He said police did not expect any riots.
Wilders, who leads the Dutch Party for Freedom (PVV), has often expressed his distaste for Islam and mass immigration. He is due to be prosecuted in his own country after leading an anti-Moroccan chant during election campaigning last year in The Hague.
He lives under police protection, for fear that his outspoken attacks on Islam could see him assassinated.
He has antagonised the Muslim world by calling for a ban on the Koran, which he likened to Adolf Hitler's Mein Kampf. However, he insists that he is not a racist and unlike other figures on the fringes of European politics, he has never been accused of anti-Semitism.
Strache has defended his invitation to Wilders and said the event is about promoting Western democratic values and has nothing to do with Islamophobia.