Patrick Kabele, 33, was found guilty of preparation of terrorist acts, at Woolwich Crown Court.
Kabele, of Willesden, north-west London, was stopped at Gatwick Airport on 20 August, as he attempted to board a flight to Sabiha Gokcen Airport in Istanbul.
Media devices which revealed his plans to fight alongside IS were seized.
Commander Dean Haydon, of the Met's Counter Terrorism Command, said: "Kabele's intention to join ISIS is made very clear in his own notes.
"Due to the good work of officers at the airport, who spotted Kabele and questioned him, as well as the investigation team who pieced the case together, we have prevented someone from travelling to fight for a terrorist group."
Kabele was also ordered to serve a further four years on licence when he is released.
A man who attempted to travel to Syria to join so-called Islamic State (IS) has been jailed for six years.