The man, in his 50s and living in the canton of St Gallen, was found guilty of supporting a criminal organization, representing acts of violence and incitement to crime and violence, according to a report in Neue Zurcher Zeitung which was subsequently confirmed by the public prosecutor's office.
Specifically, the man posted online propaganda for terrorist groups including videos of beheadings and executions, advice on planning attacks and instructions on how to make bombs.
He was also the administrator of a internet forum supporting Isis.
At the moment around 20 similar cases are pending in Switzerland, according to news agency ATS.
Most of them concern individuals suspected of associating with jihadist activities or posting online propaganda for terrorist groups.
Last November a 25-year-old Swiss man who had returned from Syria received a suspended sentence of 600 hours of community service for fighting overseas and helping a criminal organization.
In May 2014 two Iraqi brothers living in Basel received jail sentences for online terrorist propaganda.