Le Monde newspaper ran the results under a headline which brands efforts to get different religious and cultural communities to live side-by-side as a 'failure'.
Britain also has a sizable Muslim presence, with members often complaining of discrimination and prejudice.
Just as crucially, 42 per cent of French and 40 per cent of Germans consider the presence of Islamic communities 'a threat' to their national identities.
Jerome Fourquet, of IFOP, said the results 'go beyond linking immigration with security or immigration with unemployment, to linking Islam with a threat to identity'.
This has been accompanied by a highly publicised national identity debate, in which thousands have complained about the increasing influence of Muslim communities within France.
Meanwhile, Mr Sarkozy has courted the voters of hard-right parties like the National Front as he tries to reassert traditional values.
France is a secular society, but the vast majority of its inhabitants are Roman Catholics. No official figures are available, but the country is estimated to be home to around six million Muslims, many from its former North African colonies.
German federal authorities estimate their own Muslim population to be around 4.5 million, many of them Turks who emigrated in the 1960s.