Venner, who campaigned against gay marriage and Islam, shot himself in the mouth on Tuesday and died 20 minutes later, French reports said.
On Wednesday, the Femen Facebook page called on “European Nazis” to “follow the example of the ultra-right Wenner and immediately commit suicide, thereby permanently excluding themselves from the political arena in Europe.”
It added: “Hurry, on the sacrificial altar of Notre Dame, there is not so much space!”
Femen leader Inna Shevchenko told The HuffPost: "This is a message to all those who support fascism and those who honoured the memory of far-right activist who committed suicide at Notre Dame, including Marine Le Pen."
In February Femen protesters were at the same cathedral celebrating the resignation of Pope Benedict XVI.
Chanting "Bye bye Benedict" and "No more homophobe" the group banged bells with sticks and sported slogans on their naked chests which read "Crisis of faith" and "Pope no more".
FEMEN vient de mener une action sur l'autel de Notre Dame pour appeler à la mort du fascisme MAY FASCISM REST IN HELL twitter.com/Femen_France/s…— Femen France(@Femen_France) May 22, 2013
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Femen protesters at Notre Dame in February, celebrating the resignation of the Pope.