Unknown assailants hung a pig's head at the entrance to the Sukkat Shaul Synagogue in Ramat Hasharon.
Worshippers were shocked upon finding the bloody head and summoned police, who opened an investigation.
Eli Armani, the synagogue's caretaker for the past 25 years, told Hadashot that "they called me from the house because they told me there was a pig's head in the place, and I immediately came to see what happened and I was shocked to see these things.
"Not a picture or a statue - a pig's head with the flesh and blood on it. It is shocking that within us there is such a thing."
Deputy Defense Minister Eli Ben Dahan (Jewish Home) condemned the hate crime. "At the 80th anniversary of Kristallnacht, anti-Semitism is also raising its head in the Land of Israel," he said.
"The ongoing incitement against the religious community in Ramat Hasharon was a stage in the form of the head of a pig placed in front of a synagogue. We have to stop it now. "